Particles in Solids, Liquids and Gases: a full term of science
Ten ready-to-teach lessons for Year 5 Chemical sciences. Print this pack and the term is prepared: every lesson comes with a step-by-step plan, the questions to ask, a student worksheet, cut-out cards or exit tickets, an assessment kit and every answer.
Start here: five minutes to Monday
- Skim the term at a glance on the next page.
- Print the lesson you need. Each lesson is three A4 sheets: plan, worksheet, cards or tickets.
- Gather the few everyday items under “You need” on the plan. Nothing needs a science cupboard.
- Open the free interactive unit on your board or projector. Every plan tells you which picture to show and when.
- Teach straight from the plan. Timings, talk prompts, misconceptions and answers are all on the one page.
No science background needed
This pack is written for the busy generalist teacher. Each plan explains the science idea in plain words, lists the misconceptions children bring, and gives model answers. The big idea of the term: everything is made of particles far too small to see. How they are arranged and how fast they move explain what we can see: a solid keeps its shape, a liquid pours and takes the shape of its container, and a gas spreads out to fill any space and can be squeezed. Heating makes the particles move more, and that changes the state.
Two ways to run each lesson
Every lesson works as one 60-minute block, or as two 30-minute sessions. The split point is marked in every plan. Lesson 7 starts saucers that are read over three days, and Lessons 6 and 8 need ice made the day before, so look ahead when you plan.
Safety and care in one look
Warm water comes from the hot tap, never from a kettle. Syringes are plastic and have no needles. Nothing in the tests is eaten or tasted. Check for latex allergies before using balloons, and wipe up water spills at once.
The term at a glance
One lesson a week for a term. Each lesson stands on the ones before it, so run them in order where you can.
| # | Lesson | Children learn and do | You need (in short) |
|---|---|---|---|
| 1 | Solid, liquid or gas? | Test real samples for shape, pouring and filling, and sort twelve material cards by state | Samples in cups and jars, material cards from this pack |
| 2 | Be the particles | Act out a solid, a liquid and a gas, then draw each as a particle picture | Open space, particle-picture cards from this pack |
| 3 | The spreading colour | Time a drop of food colouring spreading in cold, room-temperature and warm water | Clear cups, food colouring, thermometers, a timer |
| 4 | Squeeze it | Push the plunger on syringes of air, water and sand, and measure how far each squeezes | Plastic syringes with no needles, water, dry sand |
| 5 | Air takes up space | Keep a paper towel dry under water in a cup, and pour 100 mL into different shapes | A tub of water, clear cups, paper towel, measuring jugs |
| 6 | The melting race | Race ice cubes from the same tray on a metal tray, on a plastic plate and wrapped in a cloth | Ice cubes, a metal tray, plastic plates, a cloth, a timer |
| 7 | Where did the water go? | Weigh saucers of water drying in the sun and the shade over three days, and make water appear on a cold cup | Saucers, kitchen scales, a cup of ice water |
| 8 | Nothing lost | Weigh a sealed bag of ice before and after it melts, and draw the particles at each stage | Zip-lock bags, ice, kitchen scales, warm water |
| 9 | Particles at work | Match eight everyday puzzles to the particle idea that explains each one | Particles-at-work cards, a dented table-tennis ball, warm water |
| 10 | Show what we know | Build a particle model of the three states with labels, and sit the final check | Paper plates, plasticine or paper circles, glue |
How the sequence builds
Lesson 1 sorts materials by what we can see them do. Lesson 2 brings in the particle model, and Lessons 3 to 5 test it: particles move faster when warm, a gas squeezes because of the gaps between its particles, and air takes up space. Lessons 6 to 8 explain changes of state, melting, evaporating and condensing, and show that no particles are lost. Lesson 9 uses the model to explain everyday puzzles, and Lesson 10 is the model-making task and final check.
Curriculum links (Australian Curriculum V9)
The whole term teaches the Science Understanding descriptor AC9S5U04 quoted on the cover. The lessons also work these Science Inquiry and Human Endeavour descriptors:
Assessment in this pack
- Every plan ends with “Answers and look-fors”: what meeting the idea sounds like in a Year 5 voice.
- The assessment sheet near the front has a class observation checklist and a three-level rubric.
- Lesson 10 is the summative pair: a labelled particle model of the three states, plus the “Show what we know” check sheet.
Materials for the whole term
One gathering session covers all ten lessons. Everything on this page is an everyday item or can be borrowed; nothing needs a science cupboard. Make ice the day before Lessons 1, 6 and 8, all in the same tray so the cubes match.
| Lesson | You need |
|---|---|
| 1 | samples in clear cups or jars: a wooden block, water, honey, sand and an ice cube, plus a blown-up balloon; three differently shaped containers; the material cards from this pack |
| 2 | an open space such as the hall; the particle-picture cards from this pack |
| 3 | for each group: three clear cups, food colouring, cold water from the fridge, room-temperature water, warm water from the hot tap, a thermometer and a timer |
| 4 | for each group: three plastic syringes with no needles (20 mL or bigger), water, dry sand and a tray |
| 5 | a clear tub of water deeper than a cup is tall, clear plastic cups and paper towel; for each group, a measuring jug and three or four differently shaped clear containers |
| 6 | for each group: three ice cubes made in the same tray, a metal tray, two plastic plates, a cloth such as a tea towel and a timer |
| 7 | for each group: two saucers, a measuring jug, masking tape, a marker and kitchen scales; a clear cup of ice water with a few drops of food colouring, and a paper towel |
| 8 | for each group: a zip-lock bag, three ice cubes, kitchen scales that read to 1 g, a bowl of warm water from the hot tap and paper towel |
| 9 | the particles-at-work cards from this pack, a dented table-tennis ball and a bowl of warm water from the hot tap |
| 10 | for each child: three paper plates or a card ruled into three, plasticine or paper circles, glue and coloured pencils; the interactive unit open for the class quiz |
The one-trip list
- From the classroom: thermometers, timers, measuring jugs, masking tape, markers, card, glue, coloured pencils.
- From the kitchen or the shops: food colouring, honey, zip-lock bags, plastic cups, plastic and paper plates, paper towel, balloons, plasticine.
- From home donations: dry sand, a wooden block, saucers, bowls, tea towels, a dented table-tennis ball, differently shaped clear containers, a clear tub.
- To borrow: plastic syringes with no needles (a pharmacy may donate them), kitchen scales, metal baking trays.
Safety and care in one look
- Warm water comes from the hot tap, never a kettle, and an adult pours it.
- Syringes are plastic with no needles, and are never pointed at anyone’s face.
- Nothing in the tests is eaten or tasted, including the ice.
- Check for latex allergies before using balloons.
- Wipe up water spills at once: wet floors are slippery.
Assessment without extra work
The term assesses itself. Every lesson plan ends with answers and look-fors, and Lesson 10 is the summative pair: a labelled particle model of the three states, and the check sheet. This sheet is the place to jot down what you notice along the way.
The three levels
| Idea | Working towards | At standard | Beyond |
|---|---|---|---|
| Properties | names a solid, a liquid and a gas | describes what solids, liquids and gases do: keep their shape, pour, fill a space, squeeze | sorts tricky materials, such as sand or honey, and explains the choice |
| Particle model | says things are made of tiny particles | draws and describes how the particles are arranged and move in each state | uses the model to explain a property, such as why a gas can be squeezed |
| Changes of state | names melting or evaporating | explains melting and evaporating as particles gaining energy and moving more | explains why the mass stays the same when the state changes |
| Testing | follows the steps of a test | names what was changed, measured and kept the same, and records measurements with units | compares results with another group and suggests a reason for any difference |
Class observation checklist
| Name | Properties | Particle model | Change of state | Testing | Explaining |
|---|---|---|---|---|---|
A tick a lesson is plenty; the Lesson 10 check sheet fills the gaps.
Word wall cards
Cut out the cards and build the wall as the words arrive. Lesson 1 starts the wall with solid, liquid, gas and property.
a tiny piece of matter, far too small to see
keeps its own shape
pours and takes the shape of its container
spreads out to fill any space
something a material does or is like
a way of picturing something we cannot see
to shake back and forth in one place
to squeeze into a smaller space
to change from a solid to a liquid
to change from a liquid to a solid
to change from a liquid to a gas
to change from a gas to a liquid
Dear families
This term in science, Year 5 investigates solids, liquids and gases, and the particle model that explains them. Everything is made of particles far too small to see. In a solid they are packed tightly and only vibrate; in a liquid they are close together but can slide past each other; in a gas they are far apart and move fast in every direction.
Your child will race food colouring in warm and cold water, squeeze air and water in syringes, keep a paper towel dry under water, race melting ice cubes, watch water evaporate, and weigh a bag of ice before and after it melts to find that nothing is lost.
Try this at home
- In the kitchen, find a solid, a liquid and a gas. How can you tell which is which?
- Put a drop of food colouring in a glass of cold water and another in warm tap water. Which spreads faster?
- Breathe on a cold mirror or window. Where does the mist come from?
- Hang one wet sock in the sun and one in the shade. Which dries first?
What to ask your scientist
- Is sand a solid or a liquid? How do you know?
- Why can you squeeze air but not water?
- What happens to the particles when ice melts?
- Where does a puddle go when it dries up?
A small note on care: please use warm tap water, not boiling water, for any experiments at home.
Warm regards,
The Year 5 team
Printed from the free seegongsik Particles in Solids, Liquids and Gases teaching pack · seegongsik.com/au/y5/chemical/AC9S5U04/pack
Solid, liquid or gas?
Children already know the words solid, liquid and gas; this lesson asks them how they know. They test real samples: does it keep its own shape when it is moved to another container, does it pour, does it spread to fill the whole space? Then they sort twelve material cards by state, including tricky ones such as sand, which pours but is made of tiny solid grains, and honey, which is thick but still a liquid.
We are learning to
- describe the observable properties of solids, liquids and gases,
- test materials for those properties and record the results,
- sort materials by state and explain a tricky case.
Success criteria
- I can say what a solid, a liquid and a gas each do, using our tests.
- I can explain why sand is a solid even though it pours.
You need
- samples in clear cups or jars: wooden block, water, honey, sand, ice cube, air in a balloon, and three differently shaped containers,
- the material cards (third sheet), one set per pair,
- the worksheet (next sheet), one per child.
Lesson flow (about 60 minutes)
| 5 min | How do you know? Hold up a cup of water. Ask: “Water is a liquid. How do you know? What does a liquid do that a solid does not?” |
| 10 min | On the board Show the three states in a box (see the box). Ask: “Which state fills the whole box? Which keeps its own shape?” |
| 25 min | Property tests Groups move each sample into a differently shaped container and watch: does it keep its shape, pour, take the shape of the container, spread to fill it? Fill Part A. |
| 15 min | Card sort Pairs sort the twelve cards into solids, liquids and gases, then fill Part B. Ask: “Which card was hardest to sort? What clue did you use?” |
| 5 min | Word wall Add solid, liquid, gas and property to the word wall. Children do Part C. |
Running two half-sessions instead? End Session A after the property tests; start Session B with the card sort.
Watch for these ideas
- “Sand is a liquid because it pours.” Each grain of sand is a tiny solid that keeps its shape; a heap of grains can pour.
- “Gases are not real because you cannot see them.” Air is a gas: it fills a balloon, and you feel it as wind.
- “Honey is a solid because it is thick.” Honey pours and takes the shape of its jar, slowly: it is a thick liquid.
Make it easier, make it bigger
- Easier: test three samples together as a class: the block, the water and the balloon.
- Bigger: find a material that is hard to sort, such as toothpaste or shaving foam, and explain what makes it tricky.
Answers and look-fors
- Part A, in the order keeps its shape, pours, takes the container’s shape, fills the space: wooden block, yes, no, no, no (solid); water, no, yes, yes, no (liquid); honey, no, yes, slowly, yes, no (liquid); sand, each grain does, yes, as a heap, the heap does, no (solid); ice cube, yes, no, no, no (solid); air in a balloon, no, no, yes, yes (gas).
- Part B: solids, a wooden block, sand, ice, salt; liquids, water, honey, milk, cooking oil; gass, the air in a balloon, helium in a party balloon, the bubbles in a fizzy drink, the air in a bike tyre.
- Part C: every grain of sand is a tiny solid that keeps its own shape and size; only a heap of grains pours.
What does it do?
A. Property tests
| Sample | Keeps its own shape? | Pours? | Takes the shape of its container? | Spreads to fill the whole space? | Solid, liquid or gas? |
|---|---|---|---|---|---|
| Wooden block | |||||
| Water | |||||
| Honey | |||||
| Sand | |||||
| Ice cube | |||||
| Air in a balloon |
B. Sort the cards
| Solid | Liquid | Gas |
|---|---|---|
C. The sand puzzle
Material cards
Cut out the cards. Read each clue, then sort the cards into solids, liquids and gases.
Stays a block shape on the desk or in a box.
Pours, and takes the shape of any cup.
Pours slowly from a spoon and settles flat in the jar.
Fills the balloon right out to its edges.
Pours from a bucket, but every grain keeps its shape.
Fills the balloon and makes it float up.
Pours from the carton and fills the bottom of the glass.
Rise through the drink and escape into the air.
Keeps its cube shape until it melts.
Pours from the shaker, but every grain is a tiny hard cube.
Pours and spreads across the bottom of the pan.
Is pumped in and pressed into the whole tyre.
Teacher note: nothing on the sample table is tasted. Lesson 2 zooms in on the particles inside each pile.
Be the particles
Scientists explain what solids, liquids and gases do with a model: everything is made of particles far too small to see. Children become the particles. As a solid they stand close in neat rows with arms linked, wobbling on the spot; as a liquid they stay close but unlink and slide past each other; as a gas they spread out and move quickly across the whole space. Then they draw each state as a particle picture and check six picture cards for mistakes.
We are learning to
- use a particle model to describe solids, liquids and gases,
- describe how the particles are arranged and how they move in each state,
- check a model for mistakes and correct them.
Success criteria
- I can draw the particles in a solid, a liquid and a gas, and describe how each moves.
- I can spot a mistake in a particle picture and explain it.
You need
- an open space such as the hall,
- the particle-picture cards (third sheet), one set per pair,
- the worksheet (next sheet), one per child.
Lesson flow (about 60 minutes)
| 5 min | Too small to see Pass round a grain of salt. Ask: “If you shrank smaller than this grain, what might water look like?” |
| 10 min | On the board Show how the particles sit and move (see the box). Ask: “What is different about the particles in each state: how they sit, and how they move?” |
| 15 min | Be the particles In the hall, the class becomes a solid, then a liquid, then a gas, as the teacher calls each one. Finish with ‘heat up’: everyone moves a little more each time. Back in class, fill Part A. |
| 15 min | Draw the model Children draw the particles for each state in Part B, using circles that are all the same size. |
| 15 min | Picture check Pairs check each card and fill Part C. Add particle and model to the word wall. Ask: “Which card has the mistake you would most like to fix? How would you fix it?” |
Running two half-sessions instead? End Session A after the role play; start Session B with the drawings.
Watch for these ideas
- “Ice particles are cold and hard, and water particles are wet.” The particles are the same in ice and in water; only how they are arranged and how they move changes.
- “In a gas there is air between the particles.” Between the particles of a gas there is nothing at all: empty space.
- “The particles in a solid do not move.” They vibrate on the spot all the time.
Make it easier, make it bigger
- Easier: act out and draw the solid and the gas first, then add the liquid.
- Bigger: act out melting. Start as a solid and slowly heat up until you are a gas. What changes, and what stays the same?
Answers and look-fors
- Part A: solid, close together in neat rows, arms linked, wobbling on the spot; liquid, close together but jumbled, sliding past each other; gas, spread far apart, moving fast in every direction.
- Part B: a solid as touching circles in neat rows; a liquid as touching circles, jumbled, at the bottom of the box; a gas as a few circles far apart all over the box.
- Part C: A mistake, gas particles spread out to fill the whole box, not one corner; B good model; C mistake, the particles in a solid touch; they are packed tightly, not spread out; D good model; E good model; F mistake, liquid particles stay close together, touching, and settle at the bottom.
- Bigger: the same people, the same particles, stay all the way through; only their arrangement and motion change.
The particle model
A. When we were the particles
| State | How we stood | How we moved |
|---|---|---|
| Solid | ||
| Liquid | ||
| Gas |
B. Draw the particles
C. Picture check
| Card | Good model? | If not, what is wrong? |
|---|---|---|
| A | ||
| B | ||
| C | ||
| D | ||
| E | ||
| F |
Particle-picture cards
Cut out the cards. Each card says which state it shows. Is the picture a good model of that state, or is there a mistake?
Teacher note: in every card, each circle stands for one particle, and all the particles are the same size.
The spreading colour
The particle model says that particles are always moving, and that they move faster when they are warmer. Children test it with three cups of water, cold, room temperature and warm, and one drop of food colouring in each, added at the same moment and never stirred. They time how long the colour takes to spread through each cup. The colour usually spreads fastest in the warm water, because its fast-moving particles knock the colour around and carry it through the cup.
We are learning to
- describe particles as always moving, and moving faster when warmer,
- run a fair test, measure temperature and time, and graph the results,
- use the particle model to explain what we saw.
Success criteria
- I can say in which cup the colour spread fastest, using our times.
- I can explain why, using the words particles and moving.
You need
- for each group: three clear cups with 200 mL of water in each, cold from the fridge, at room temperature, and warm from the hot tap,
- food colouring, a thermometer and a timer,
- the worksheet (next sheet) and the exit tickets (third sheet).
Lesson flow (about 60 minutes)
| 5 min | Cordial question Talk about making a drink. Ask: “Does cordial mix faster in warm water or in cold water? Why might that be?” |
| 10 min | On the board Show heat making particles move more (see the box). Ask: “If warmer particles move more, what might happen to a drop of colour in warm water?” |
| 25 min | The colour race Groups measure the temperature of each cup, then add one drop of colour to each at the same moment, without stirring. They time how long until no clear water is left in each cup, stopping at 10 minutes, and fill Parts A and B. |
| 10 min | Graph it Children draw the column graph in Part C. Ask: “What pattern do the three bars show?” |
| 10 min | Explain it Children explain the pattern with particles in Part D, then fill an exit ticket. |
Running two half-sessions instead? End Session A after the colour race; start Session B with the graph.
Watch for these ideas
- “The colour just sinks because it is heavy.” The drop sinks at first, but then it spreads out because the moving water particles knock it about.
- “Spreading is the same as stirring.” Stirring mixes it faster with our help; in this test nobody stirs, so only the particles do the mixing.
- “Particles in cold water stop moving.” They still move, just more slowly.
Make it easier, make it bigger
- Easier: race two cups only, cold and warm.
- Bigger: add a fourth cup at a temperature in between. Predict where its bar will go, then test it.
Answers and look-fors
- Part A: we change the temperature of the water; we measure the time for the colour to spread through the cup; we keep the same the amount of water, the cups, the size of the drop, the start time, and nobody stirs.
- Parts B and C: times vary. Usually the colour spreads fastest in the warm water, then in the room-temperature water, and slowest in the cold water, which may not finish within 10 minutes.
- Part D: in warm water the particles move faster, so they bump the colour around and spread it through the cup sooner.
- Exit tickets: 1 warm. 2 any one of the amount of water, the cups, the drop size, the start time or no stirring. 3 particles move faster when they are warmer.
The colour race
A. Our fair test
B. Our results
| Cup | Temperature (°C) | Time to spread (minutes) |
|---|---|---|
| Cold | ||
| Room temperature | ||
| Warm |
C. Our graph
D. Explain it with particles
Exit tickets
Print one sheet for every four children and cut along the dashed lines. Each child answers a ticket alone before leaving.
1. Circle one. The colour spread fastest in the ( cold / warm ) water.
2. One thing we kept the same: ______________
3. Finish the sentence: when particles are warmer, they
1. Circle one. The colour spread fastest in the ( cold / warm ) water.
2. One thing we kept the same: ______________
3. Finish the sentence: when particles are warmer, they
1. Circle one. The colour spread fastest in the ( cold / warm ) water.
2. One thing we kept the same: ______________
3. Finish the sentence: when particles are warmer, they
1. Circle one. The colour spread fastest in the ( cold / warm ) water.
2. One thing we kept the same: ______________
3. Finish the sentence: when particles are warmer, they
Teacher note: the answers are on this lesson’s plan. Food colouring stains; wipe spills straight away.
Squeeze it
A gas can be squeezed into a smaller space, but a solid or a liquid hardly squeezes at all. Children test it with plastic syringes of air, water and dry sand: they block the tip, push the plunger and read how far it went. Air squeezes a lot, because there are big empty gaps between its particles; water barely squeezes, because its particles already touch; sand squeezes only until the air between its grains is gone. Then they sort nine things into those that squeeze and those that hardly do.
We are learning to
- use the particle model to explain why a gas can be squeezed and a liquid cannot,
- read a scale in millilitres and work out a difference,
- explain a tricky case, such as sand or a sponge.
Success criteria
- I can say how far each syringe squeezed, in millilitres.
- I can explain why the air squeezed most, using the word gaps.
You need
- for each group: three plastic syringes with no needles (20 mL or bigger), water, dry sand and a tray,
- the squeeze-or-not cards (third sheet), one set per pair,
- the worksheet (next sheet), one per child.
Lesson flow (about 60 minutes)
| 5 min | Pump it up Hold up a bike pump or a ball. Ask: “A pump pushes more and more air into a tyre. Where does it all fit?” |
| 10 min | On the board Push the lid on each state (see the box). Ask: “Why does the lid move so far on the gas, and hardly at all on the liquid?” |
| 20 min | Syringe test Over the tray, groups fill each syringe to the 20 mL mark (with air, water or sand), block the tip firmly with a finger, push the plunger as far as it will go and read the new mark. Fill Part A. |
| 10 min | Particle pictures Children draw the air particles before and after squeezing in Part B. |
| 15 min | Squeeze or not? Pairs sort the nine cards and answer Parts C and D. Add compress to the word wall. Ask: “A sponge is a solid, but it squeezes. What is inside it that squeezes?” |
Running two half-sessions instead? End Session A after the syringe test; start Session B with the drawings.
Watch for these ideas
- “The air got used up when we squeezed it.” The same air particles are still in the syringe, just closer together; let go and the plunger springs back.
- “Water can be squeezed if you push hard enough.” Water squeezes so little that we cannot see it, because its particles already touch.
- “The sand squeezed, so solids can be squeezed.” Only the air between the grains squeezed; the grains themselves did not.
Make it easier, make it bigger
- Easier: test air and water only.
- Bigger: fill a syringe half with water and half with air. Predict how far it will squeeze, then test it.
Answers and look-fors
- Part A: readings vary. Usually the air squeezes a lot, often to half its space or less; the water hardly moves; the sand squeezes a little.
- Part B: before, a few particles spread right through the syringe; after, the same number of particles, much closer together.
- Part C: the air, because there are big empty gaps between gas particles, so they can be pushed closer together.
- Part D: the sand grains are solid and do not squeeze, but there is air between them, and that air squeezes until the grains touch.
- Cards: squeeze, 1, 4, 5, 8, 9; hardly squeeze, 2, 3, 6, 7. The sponge and the marshmallow squeeze because of the air in their holes and bubbles.
How much does it squeeze?
A. The syringe test
| Syringe of | Start (mL) | After pushing (mL) | Squeezed by (mL) |
|---|---|---|---|
| Air | 20 | ||
| Water | 20 | ||
| Dry sand | 20 |
B. The air particles
C. Which squeezed most?
D. The sand puzzle
Squeeze or not?
Cut out the cards. Sort them into things that can be squeezed into a smaller space and things that hardly squeeze at all.
The air in a bike pump
The water in a garden hose
A block of wood
A kitchen sponge
The air in a scuba diver’s tank
Milk in a carton
A stone
A marshmallow
The air in a football
Teacher note: syringes are pushed over the tray and never pointed at anyone. Rinse the sand out of them after the lesson.
Air takes up space
Air is a gas, and a gas is made of particles too, so air takes up space even though we cannot see it. Children wedge a scrunched paper towel into the bottom of a cup, turn the cup upside down and push it straight down into a tub of water. The towel stays dry: the cup is full of air, and the air keeps the water out. Tip the cup under the water and bubbles of air escape, the water rushes in and the towel gets wet. Then they pour 100 mL of water into differently shaped containers. The water takes each new shape, but it is still 100 mL when it goes back in the jug.
We are learning to
- show that air is a gas that takes up space,
- describe how a liquid takes the shape of its container but keeps the same volume,
- compare solids, liquids and gases by their shape and the space they take up.
Success criteria
- I can explain why the paper towel stayed dry, using the word air.
- I can say what changed and what stayed the same when the water went into a new shape.
You need
- a clear tub of water deeper than a cup is tall, clear plastic cups and paper towel,
- a measuring jug and three or four differently shaped clear containers for each group,
- the worksheet (next sheet) and the exit tickets (third sheet).
Lesson flow (about 60 minutes)
| 5 min | Is it empty? Hold up an empty cup. Ask: “Is this cup empty? Is there anything in it at all?” |
| 15 min | The dry towel Groups wedge a scrunched paper towel into the bottom of a cup so it stays put when the cup is turned over. They predict, push the cup straight down to the bottom of the tub, hold it there, then lift it straight out and feel the towel. Next, they push it down again and tip it under the water. Fill Parts A and B. |
| 10 min | On the board Compare a liquid and a gas in the same box (see the box). Ask: “The same particles are in the box each time. Why does the gas fill the whole box?” |
| 20 min | Same water, new shape Groups measure 100 mL of water in the jug, pour it into each container in turn, draw its shape, then pour it back into the jug and read it again. Fill Part C. |
| 10 min | Shape and space Children fill the table in Part D, then an exit ticket. Ask: “Which state keeps its shape and its space, and which keeps neither?” |
Running two half-sessions instead? End Session A after the dry towel; start Session B on the board.
Watch for these ideas
- “The cup was empty, so the water should have got in.” The cup was full of air. Air particles take up space, so the water could not get in until the air escaped.
- “The bubbles are empty holes in the water.” Each bubble is air: gas particles escaping from the cup and rising to the top.
- “The tall container has more water in it, because the water is higher.” The water is taller but thinner; back in the jug it is still 100 mL.
Make it easier, make it bigger
- Easier: run the dry-towel test as a class demonstration, with children predicting each step.
- Bigger: hold a second cup upside down under the water, full of water. Tip the air-filled cup beneath it so the bubbles rise into it. Can you pour air from one cup into another under water?
Answers and look-fors
- Part A: the towel stays dry, because the cup is full of air, and the air takes up the space so the water cannot get in. A good drawing shows the cup upside down under the water, air filling the cup around the towel, and the water stopping at the rim.
- Part B: bubbles rise when the cup tips. The air escapes, the water takes its place, and the towel gets wet.
- Part C: the water takes the shape of each container, but back in the jug it is still 100 mL, or just under if a few drops stay behind.
- Part D: solid, keeps its shape yes, keeps the same space yes; liquid, keeps its shape no, it takes the shape of its container, keeps the same space yes; gas, keeps its shape no, it spreads to fill its container, keeps the same space no, it spreads to fill any space and can be squeezed.
- Exit tickets: 1 air. 2 100 mL. 3 it keeps the same amount, or volume.
Where is the air?
A. The dry paper towel
B. Tip the cup
C. Same water, new shape
| Container (100 mL poured in) | Draw the shape of the water | Back in the jug (mL) |
|---|---|---|
| Tall, thin container | ||
| Short, wide container | ||
| Container with corners | ||
| Our own choice |
D. Shape and space
| State | Keeps its own shape? | Keeps the same amount of space? |
|---|---|---|
| Solid | ||
| Liquid | ||
| Gas |
Exit tickets
Print one sheet for every four children and cut along the dashed lines. Each child answers a ticket alone before leaving.
1. Circle one. The towel stayed dry because the cup was full of ( water / air ).
2. 100 mL of water is poured into a tall, thin glass. How much water is in the glass? ______ mL
3. Finish the sentence: a liquid takes the shape of its container, but
1. Circle one. The towel stayed dry because the cup was full of ( water / air ).
2. 100 mL of water is poured into a tall, thin glass. How much water is in the glass? ______ mL
3. Finish the sentence: a liquid takes the shape of its container, but
1. Circle one. The towel stayed dry because the cup was full of ( water / air ).
2. 100 mL of water is poured into a tall, thin glass. How much water is in the glass? ______ mL
3. Finish the sentence: a liquid takes the shape of its container, but
1. Circle one. The towel stayed dry because the cup was full of ( water / air ).
2. 100 mL of water is poured into a tall, thin glass. How much water is in the glass? ______ mL
3. Finish the sentence: a liquid takes the shape of its container, but
Teacher note: the answers are on this lesson’s plan. Wipe up water spills at once: wet floors are slippery.
The melting race
Ice melts when its particles gain enough energy to break free of their places. The energy comes as heat from the warm room around the ice. Children race three ice cubes from the same tray: one on a metal tray, one on a plastic plate, and one wrapped in a cloth on a plastic plate. Metal lets the room’s heat flow into the ice quickly, so that cube usually melts first; the cloth slows the heat down, so the wrapped cube lasts longest. Many children predict the opposite, because a cloth ‘keeps things warm’. That surprise is the heart of the lesson.
We are learning to
- explain melting as particles gaining energy, vibrating more and breaking free to slide,
- run a fair test and record a change over time,
- explain why some materials keep ice frozen for longer.
Success criteria
- I can say which cube melted first and which lasted longest, using our results.
- I can explain melting with particles, using the words vibrate and slide.
You need
- for each group: three ice cubes made in the same tray, a metal tray, two plastic plates, a cloth such as a tea towel, and a timer,
- the worksheet (next sheet) and the exit tickets (third sheet).
Lesson flow (about 60 minutes)
| 5 min | Start the race Children write their predictions in Part A. Then, at the same moment, each group puts one cube on the metal tray, one on a plastic plate, and one wrapped in the cloth on the other plate, side by side and out of the sun. Start the timer. |
| 10 min | On the board Show heat breaking up a solid (see the box). Keep checking the cubes every 5 minutes. Ask: “What do the particles in the ice need, to break free of their places? Where can our ice get it from?” |
| 25 min | Check and draw At every 5-minute mark, children look at each cube (unfold the cloth quickly and wrap it again) and fill a row of Part B. Between checks they draw the particles in Part C and answer Part D. |
| 10 min | Which lasted longest? At 45 minutes, compare results across the groups. Ask: “Did the cloth keep its cube warm, or cold? How can a cloth do both jobs?” |
| 10 min | Explain it Children answer Part E and fill an exit ticket. Add melt, freeze and vibrate to the word wall. Leave any cube that is still ice and check it at the end of the day. |
Running two half-sessions instead? Start the race at the beginning of Session A and end it after the 45-minute check; start Session B with the comparison.
Watch for these ideas
- “The cloth will melt the ice fastest, because cloth keeps things warm.” A cloth makes no heat. It slows heat moving in or out, so it keeps a warm body warm and a cold ice cube cold.
- “The metal feels cold, so its ice will melt slowest.” Metal feels cold because it takes heat from your hand quickly; for the same reason it passes heat to the ice quickly.
- “When ice melts, it turns into a different stuff.” Ice and water are the same particles; melting only changes how they are arranged and how they move.
Make it easier, make it bigger
- Easier: race two cubes only, one on the metal tray and one wrapped in the cloth.
- Bigger: design the best ice keeper. Which classroom material keeps a cube frozen longest? Plan a fair test to find out.
Answers and look-fors
- Part A: predictions vary. Many children predict that the cloth melts its cube fastest.
- Part B: times vary with the room. Usually the cube on the metal tray melts first, then the one on the plastic plate, and the cube in the cloth lasts longest, often still part ice at 45 minutes.
- Part C: ice, touching particles in neat rows; melting, the rows breaking up at the edges; water, particles still touching but jumbled, at the bottom. The same number of particles in all three.
- Part D: when water freezes, its particles lose energy, move more slowly and settle into fixed places in neat rows.
- Part E: metal lets heat from the room flow into the ice fastest, so the particles there vibrate harder and break free sooner; the cloth slows the heat down, so its cube lasts longest.
- Exit tickets: 1 usually the metal tray. 2 they vibrate more and more, until they break free of their places and slide past each other. 3 the cloth slows the heat from the room getting to the ice.
The melting race
A. Our predictions
B. The race
At each check, write C (still a cube), P (part melted) or M (all melted).
| Time (minutes) | Metal tray | Plastic plate | In the cloth |
|---|---|---|---|
| 5 | |||
| 10 | |||
| 15 | |||
| 20 | |||
| 25 | |||
| 30 | |||
| 35 | |||
| 40 | |||
| 45 |
C. Draw the particles
D. Freezing
E. Explain the race
Exit tickets
Print one sheet for every four children and cut along the dashed lines. Each child answers a ticket alone before leaving.
1. Circle one. The ice melted fastest on the ( metal tray / plastic plate / cloth ).
2. Finish the sentence: as ice warms up, its particles
3. Why does a cloth keep an ice cube frozen for longer?
1. Circle one. The ice melted fastest on the ( metal tray / plastic plate / cloth ).
2. Finish the sentence: as ice warms up, its particles
3. Why does a cloth keep an ice cube frozen for longer?
1. Circle one. The ice melted fastest on the ( metal tray / plastic plate / cloth ).
2. Finish the sentence: as ice warms up, its particles
3. Why does a cloth keep an ice cube frozen for longer?
1. Circle one. The ice melted fastest on the ( metal tray / plastic plate / cloth ).
2. Finish the sentence: as ice warms up, its particles
3. Why does a cloth keep an ice cube frozen for longer?
Teacher note: the answers are on this lesson’s plan. Nothing is tasted, including the ice. Wipe up meltwater at once.
Where did the water go?
A puddle dries up without ever boiling. Even in cool water some particles at the surface move fast enough to escape into the air as an invisible gas, water vapour: the water evaporates. Warmer water has more fast particles, so it evaporates faster. Children start two saucers of water, one in the sun and one in the shade, and weigh them each day for three days. Then the reverse: water vapour in the air touches a cup of ice water, cools, and condenses into drops on the outside of the cup.
We are learning to
- explain evaporating and condensing with the particle model,
- measure mass on kitchen scales and work out how much water is left,
- sort everyday changes into melting, freezing, evaporating and condensing.
Success criteria
- I can say which saucer lost water faster, using our measurements.
- I can explain where the drops on the cold cup came from.
You need
- for each group: two saucers, a measuring jug, masking tape, a marker and kitchen scales,
- a clear cup of ice water with a few drops of food colouring, and a paper towel,
- the change-of-state cards (third sheet), one set per pair, and the worksheet (next sheet), one per child.
Lesson flow (about 60 minutes)
| 5 min | Puddle puzzle Talk about the playground after rain. Ask: “The puddles are gone by the afternoon. Where did the water go?” |
| 15 min | Set up the saucers Groups label two saucers Sun and Shade on masking tape and weigh each one empty. They pour 50 mL of water into each, weigh them again and fill the Day 0 row of Part A. One saucer goes on a sunny windowsill, the other in a shady spot in the room. |
| 10 min | On the board Show heat turning a liquid into a gas (see the box). Ask: “Our saucers will never boil. So how can their water still leave as a gas?” |
| 10 min | The cold cup Stand the cup of coloured ice water on a paper towel. After a few minutes, drops form on the outside. Wipe a few with the paper towel: they are clear. Fill Part B. |
| 20 min | Change-of-state cards Pairs sort the twelve cards and record them in Part C. Add evaporate and condense to the word wall. Ask: “Which two changes are opposites of each other? Which two more?” |
Days 1, 2 and 3: about five minutes a day. Weigh both saucers at about the same time and fill a row of Part A. On day 3, children draw the graph in Part D and answer Part E.
Running two half-sessions instead? End Session A after the saucers are set up; start Session B on the board.
Watch for these ideas
- “The water disappeared.” The water particles are still there, spread through the air as an invisible gas.
- “The drops on the cold cup leaked through the cup.” The water inside is coloured but the drops are clear, and drops form above the water line too, so they came from the air.
- “Water only evaporates in the sun.” The shade saucer loses water too, just more slowly; water evaporates at any temperature, and faster when it is warmer.
Make it easier, make it bigger
- Easier: instead of weighing, trace the edge of the water on each saucer with a whiteboard marker every day, and watch the rings shrink.
- Bigger: water vapour is invisible. So what is the white mist above a hot shower? Explain it with particles.
Answers and look-fors
- Part A: 50 mL of water has a mass of about 50 g. Masses vary, but both saucers lose water each day; the sun saucer usually loses it faster and may be dry by day 3, while the shade saucer still holds some.
- Part B: the drops came from the air. Water vapour in the air touched the cold cup, cooled and condensed into drops of liquid water. The drops are clear, not coloured, so they did not come through the cup.
- Part C: melting, 2, 7, 12; freezing, 5, 9, 10; evaporating, 1, 6, 8; condensing, 3, 4, 11.
- Part D: two lines that slope down from about 50 g; the sun line usually slopes down more steeply.
- Part E: the sun saucer lost water faster, because warmer water particles move faster, so more of them escape from the surface into the air as a gas. The shade saucer lost water too, just more slowly.
- Bigger: the white mist is tiny drops of liquid water. The invisible water vapour cools in the air above the shower and condenses.
Where did the water go?
A. The drying saucers
| Day | Sun: saucer and water (g) | Sun: water left (g) | Shade: saucer and water (g) | Shade: water left (g) |
|---|---|---|---|---|
| 0 | ||||
| 1 | ||||
| 2 | ||||
| 3 |
B. The cold cup
C. Sort the cards
| Melting | Freezing | Evaporating | Condensing |
|---|---|---|---|
D. Our graph (day 3)
Draw one line for the sun saucer and one for the shade saucer. Label each line.
E. Explain it with particles (day 3)
Change-of-state cards
Cut out the cards. Is each one melting, freezing, evaporating or condensing? Sort them into four piles.
Wet washing dries on the line.
An ice block drips on a hot day.
The bathroom mirror mists up after a shower.
Drops form on a cold can from the fridge.
Water in an ice-cube tray turns to ice in the freezer.
A puddle dries up in the sun.
Butter goes runny in a hot pan.
Sweat dries on your skin after a run.
Melted chocolate sets hard in the fridge.
A puddle turns to ice on a frosty morning.
Dew forms on the grass overnight.
Candle wax goes runny near the flame.
Teacher note: there are three cards for each change. Keep the saucers out of reach of anyone who might tip them, and wipe up spills at once.
Nothing lost
When ice melts, its particles move more and change how they are arranged, but no particles are lost and none are made. So the mass stays the same. Children seal 3 ice cubes in a zip-lock bag, weigh it, melt the ice in a bowl of warm tap water and weigh the bag again. The scales show the same mass, or within 1 g. Then they solve a puzzle from Lesson 7: the open saucers lost mass, so why did the sealed bag not?
We are learning to
- explain that a change of state does not lose or make any particles, so the mass stays the same,
- weigh carefully and explain why a reading might be out by a little,
- use the particle model to explain the difference between an open saucer and a sealed bag.
Success criteria
- I can say what happened to the mass of the bag when the ice melted, using our results.
- I can explain why, using the word particles.
You need
- for each group: a zip-lock bag, 3 ice cubes, kitchen scales that read to 1 g, a bowl of warm water from the hot tap and paper towel,
- the worksheet (next sheet) and the exit tickets (third sheet).
Lesson flow (about 60 minutes)
| 5 min | Heavier or lighter? Hold up a bag of ice. Ask: “When this ice melts, will the bag be heavier, lighter or the same? Why do you think so?” |
| 10 min | Weigh the ice Children fill Part A. Groups put 3 ice cubes in a bag, press out most of the air and seal it. They dry the outside with paper towel, weigh it straight away and fill the first row of Part B. |
| 10 min | On the board Count the particles before and after melting (see the box). Ask: “Did any particles leave the box? Were any new ones made?” |
| 15 min | Melt it Groups sit the sealed bag in the bowl of warm water, with the zip above the water, until all the ice has melted, usually about 10 minutes. Meanwhile they draw the particles in Part C. |
| 10 min | Weigh the water Groups dry the bag well, weigh it again and finish Part B. Compare results across the groups. Ask: “One group’s bag is 1 g heavier. What might have caused that?” |
| 10 min | Nothing lost Children answer Part D, then an exit ticket. |
Running two half-sessions instead? End Session A after the first weighing and keep the bags in a freezer; start Session B by melting them.
Watch for these ideas
- “Ice floats, so it is lighter, and the bag will get heavier when it melts.” Ice takes up a little more space than the water it came from, which is why it floats, but its mass is the same.
- “Some of the ice is gone, so the bag will be lighter.” The ice changed state; every particle is still in the bag.
- “Water that evaporates weighs nothing.” The particles still have mass; in Lesson 7 they left the saucer and went into the air.
Make it easier, make it bigger
- Easier: weigh one bag as a class, with children reading the scales in turn.
- Bigger: seal a few spoonfuls of water in a bag and weigh it. Leave it in the sun for an hour. What forms on the inside of the bag? Has the mass changed?
Answers and look-fors
- Part A: predictions vary. Many children predict lighter, because water seems lighter than ice.
- Part B: the two masses are the same, or 1 g apart at most. A 1 g difference can come from reading the scales or from drops left on the outside of the bag.
- Part C: the same 12 particles in all three drawings: neat rows for the ice, rows breaking up as it melts, and jumbled at the bottom of the bag for the water.
- Part D: in the open saucers, water particles escaped into the air as a gas, so the mass went down. The sealed bag let no particles out and none were made, so its mass stayed the same.
- Exit tickets: 1 90 g. 2 are the same particles; they move more and slide past each other, and none are lost or made. 3 water on the outside of the bag would add to its mass.
- Bigger: drops form on the inside of the bag as the water evaporates and condenses again, but the mass stays the same.
Is anything lost?
A. Predict
B. Our weighings
| Mass (g) | |
|---|---|
| Bag of ice at the start | |
| Bag of water at the end | |
| Difference |
C. Draw the particles
Draw 12 particles in each bag.
D. The saucer puzzle
Exit tickets
Print one sheet for every four children and cut along the dashed lines. Each child answers a ticket alone before leaving.
1. Circle one. A sealed bag of ice has a mass of 90 g. When the ice melts, its mass is ( less than 90 g / 90 g / more than 90 g ).
2. Finish the sentence: when ice melts, the particles
3. Why do we dry the bag before we weigh it?
1. Circle one. A sealed bag of ice has a mass of 90 g. When the ice melts, its mass is ( less than 90 g / 90 g / more than 90 g ).
2. Finish the sentence: when ice melts, the particles
3. Why do we dry the bag before we weigh it?
1. Circle one. A sealed bag of ice has a mass of 90 g. When the ice melts, its mass is ( less than 90 g / 90 g / more than 90 g ).
2. Finish the sentence: when ice melts, the particles
3. Why do we dry the bag before we weigh it?
1. Circle one. A sealed bag of ice has a mass of 90 g. When the ice melts, its mass is ( less than 90 g / 90 g / more than 90 g ).
2. Finish the sentence: when ice melts, the particles
3. Why do we dry the bag before we weigh it?
Teacher note: the answers are on this lesson’s plan. Warm water comes from the hot tap, never a kettle. Nothing is tasted.
Particles at work
A good model explains things we have never tested. Children bring together the particle ideas of the term as four cards, A to D, then use them on eight everyday puzzles, from drying washing to a thermometer. The lesson opens with a puzzle they can watch: a dented table-tennis ball goes into warm tap water and the dent pops out, because the air inside warms up, its particles move faster and push harder on the inside of the ball.
We are learning to
- use the particle model to explain everyday things we observe,
- choose the particle idea that fits each puzzle and say why,
- write an explanation that links what we see to what the particles do.
Success criteria
- I can match each puzzle card to the particle idea that explains it.
- I can explain one puzzle in my own words, starting with the particles.
You need
- a dented table-tennis ball (dented, not cracked) and a bowl of warm water from the hot tap,
- the particles-at-work cards (third sheet), one set per pair,
- the worksheet (next sheet), one per child.
Lesson flow (about 60 minutes)
| 10 min | The dented ball Pass the dented ball round, then drop it into the warm water and wait. Ask: “Nobody touched the dent. What pushed it out?” |
| 10 min | On the board Revisit the term’s ideas (see the box) and read the four ideas in Part A together. Ask: “Which idea explains the dented ball?” |
| 20 min | Match the puzzles Pairs read each card, decide which idea explains it and write its number in the table in Part A. Each idea explains two cards. |
| 10 min | Explain one Children choose one card and explain it in Part C, starting with the particles. Ask: “Which card was the hardest to match? What made you sure in the end?” |
| 10 min | Puzzle swap Children write a puzzle of their own in Part D and swap it with a partner, who names the idea that explains it. |
Running two half-sessions instead? End Session A after the card matching; start Session B with the explanations.
Watch for these ideas
- “The particles of the ball got bigger in the warm water.” The particles stay the same size; the warm air particles move faster and push harder.
- “Smell travels because it is a liquid.” We smell a gas; its particles spread out through the air until some reach our nose.
- “Every puzzle about heat is idea D.” Read each card closely: the ice cube card is about the solid keeping its shape until it melts.
Make it easier, make it bigger
- Easier: give each pair four cards first, one for each idea, then the other four.
- Bigger: a cracked table-tennis ball will not pop out in warm water. Explain why, using particles.
Answers and look-fors
- Part A: A, cards 4 and 7; B, cards 2 and 8; C, cards 3 and 5; D, cards 1 and 6.
- Part B: the air inside the ball warms up, so its particles move faster and push harder on the inside of the ball, and that pushes the dent out (idea D).
- Part C, for example: card 1, warmer water particles move faster, so more of them escape into the air; card 2, the milk particles slide past each other, so the milk flows and spreads; card 3, the smell is a gas, and its particles spread out through the air of the house; card 4, the brick particles are held in place, so the brick keeps its shape; card 5, there are big gaps between the air particles, so they can be pushed closer together; card 6, the warmer particles move faster and spread out a little, so the liquid takes up more room; card 7, the particles in the ice are held in place until heat lets them break free; card 8, the water particles slide past each other and settle into the shape of the tray.
- Part D: any everyday example that one idea explains, such as a balloon left in a hot car growing tighter (D), or a sponge squashing because of the air in its holes (C).
- Bigger: the warm air particles escape through the crack instead of pushing the dent out.
Particles at work
A. Four particle ideas
Write the numbers of the two cards that each idea explains.
| Idea | What the particles do | Cards |
|---|---|---|
| A | In a solid, the particles are packed tightly and held in place. They can only vibrate. | |
| B | In a liquid, the particles are close together but can slide past each other. | |
| C | In a gas, the particles are far apart, with big gaps, and spread out to fill any space. | |
| D | When particles get warmer, they move faster and spread out a little more. |
B. The dented ball
C. Explain one card
D. A puzzle of my own
Particles-at-work cards
Cut out the cards. Which particle idea, A, B, C or D, explains each one? Each idea explains two cards.
Wet washing dries faster on a warm day.
Spilt milk spreads out across the table.
You can smell toast cooking from the next room.
A brick keeps its shape, even at the bottom of a wall.
A bike pump squeezes lots of air into a tyre.
The red liquid in a thermometer climbs up the tube when it gets warmer.
An ice cube keeps its cube shape until it melts.
Water fills every corner of an ice-cube tray.
Teacher note: the dented ball works best with a gentle dent. Warm water comes from the hot tap, never a kettle.
Show what we know
The summative lesson, run as a celebration. Each child builds a particle model of the three states on three paper plates, with 12 plasticine balls or paper circles on each plate, so the model shows the same particles arranged three ways. Labels and arrows say how the particles are arranged, how they move, and one property each state has. Children gallery-walk the models, sit the final check alone, and close with the on-screen quiz as a class game.
We are learning to
- model the arrangement and motion of particles in solids, liquids and gases,
- use the model to explain a property of each state,
- show what we know on our own on the final check.
Success criteria
- My model shows the same 12 particles in each state, with labels for how they are arranged and how they move.
- I can show on the final check how the particle model explains what solids, liquids and gases do.
You need
- for each child: three paper plates or a card ruled into three, 36 plasticine balls or paper circles, glue and coloured pencils,
- the worksheets and cards from the term for ideas,
- the model plan (next sheet) and the final check (third sheet), one each per child, and the interactive unit open for the closing quiz.
Lesson flow (about 60 minutes)
| 10 min | Brief and plan Set the task: a particle model of a solid, a liquid and a gas. Children plan each state on the worksheet. Ask: “What must your model show about the particles in each state: where they sit, and how they move?” |
| 20 min | Build the model Children glue 12 particles on each plate, then add arrows for the movement and a label for each state. |
| 10 min | Gallery walk Half the class stands by their models while the other half visits, then swap. Visitors count the particles on each plate and check the labels. Ask: “Which model shows the movement most clearly? How does it do that?” |
| 10 min | Final check Hand out the final check. Children work alone. Read each item aloud once; help with reading, not with answers. |
| 10 min | The class quiz Run the unit quiz on the board as a whole-class game (see the box). Ask: “One last time: when ice melts, what changes and what stays the same?” |
Running two half-sessions instead? End Session A after building the models and keep them safe. Start Session B with the gallery walk, then the final check and the class quiz.
Watch for these ideas
- Particles made bigger for the gas, or smaller for the solid. Ask: do the particles change, or only how they sit and move? Every particle is the same size.
- A liquid with big gaps like a gas. Ask: in Lesson 4, did the water squeeze? What does that tell us about its particles?
- A solid with no movement shown. Ask: what were you doing when you were the solid in Lesson 2?
Make it easier, make it bigger
- Easier: build the solid and the gas first, then add the liquid with a partner.
- Bigger: add a fourth plate that shows one change of state, melting or evaporating, with arrows that show what happens to the particles.
Answers and look-fors
- Final check marking guide: 1 the air in a tyre. 2 all the circles the same size: a solid as touching circles in neat rows, a liquid as touching circles jumbled at the bottom, a gas as a few circles far apart all over the box. 3 there are big gaps between air particles. 4 in warm water the particles move faster, so they knock the colour around and spread it sooner. 5 they move more and slide past each other. 6 85 g, because the same particles are still in the bag: none got out and none were made. 7 in the sun the water particles are warmer and move faster, so more of them escape into the air as a gas. 8 water vapour in the air touches the cold glass, cools and condenses into drops of liquid water.
- A score of 6 or more out of 8, plus a model that shows the three arrangements with the same number of particles and correct labels, meets the descriptor. The rubric near the front of the pack turns this into a level.
- Meeting the idea at the gallery sounds like “in the gas the particles are far apart and zoom around, so it spreads out to fill the room and you can squeeze it”.
My particle model plan
Plan each plate: how the 12 particles sit, how they move, and one thing that state does that the particles explain.
| State | How the particles are arranged | How they move | A property this explains |
|---|---|---|---|
| Solid | |||
| Liquid | |||
| Gas |
Show what we know
Show what you know about solids, liquids and gases. Read each one, then circle, write or draw. Take your time.
Teacher note: read the items aloud one at a time. The marking guide is on this lesson’s plan; the rubric near the front of the pack turns the score into a level.