Changing Materials

Year 2 Science · Chemical sciences · a ready-to-teach pack for one Science Understanding topic. Print it, and you have the lesson and the worksheets in hand.

The big idea

You can change the shape or size of a material by bending, twisting, stretching or breaking it. The material stays the same. Only its shape or size has changed.

What you need

• soft modelling dough or playdough
• a few sheets of paper
• drinking straws and a soft pipe cleaner or wire
• a rubber band and a sponge
• a dry biscuit or cracker, and a small cloth or towel

How the lessons flow (about one term)

• Engage: show everyday objects. Ask what we can do to change their shape.
• Explore: at four stations, children bend, twist, stretch and break real materials and record what they see (Worksheets A and B).
• Explain: build the idea together -- the shape changed, but the material did not.
• Elaborate: sort changes you can undo from changes you cannot (Worksheet C).
• Evaluate: draw and label a change, then the exit ticket (Worksheets D and the exit ticket).

Words to use

material, shape, bend, twist, stretch, break, change, change back.

Watch for these ideas

• A child may think that if something looks different it must be a different material. Gently check: it is the same stuff, only a new shape.
• A child may think breaking makes new material. The pieces are smaller, but they are still the same material.

Keep it safe

Break only soft or crumbly things, and only with care. Nothing goes in mouths. An adult helps with anything stiff.

Let’s talk about changing shapes

Hold up each object. Let the children predict before you try it.

Talk about it

• Have you ever bent a straw? What happened to it?
• What could we do to a ball of dough to change its shape?
• If we change the shape, is it still the same stuff inside?

Match the word to the action

Draw a line from each word to the action that matches it.

Observe the change

Do each action to a material. Draw what it looked like after. Then tick if it is still the same material.

Predict, test, record

Choose an action for each object. Guess first, then try it, then write what happened.

One thing I noticed

Can you change it back?

Write or draw each thing in the right box. Some changes you can undo. Some you cannot.

Things to sort: a bent straw, a stretched rubber band, squashed dough, a broken biscuit, torn paper.

Draw and label a change

Pick a material. Draw it before and after you change its shape. Then fill in the words.

Four stations

Cut along the lines. Put one card at each table. Children try the action and answer the question together.

Words we learned

Draw a line from each word to what it means.

Exit ticket

1. When you bend a straw, does it turn into a new material?   Yes  □   No  □

2. You break a biscuit into pieces. The pieces are made of the same thing / a new thing. (circle one)

Answer key

Worksheet C -- Can you change it back?

• Can change it back: a bent straw, a stretched rubber band, squashed dough (you can reshape it).
• Cannot easily change it back: a broken biscuit, torn paper.
• Either answer is fine if a child can explain their reason -- the talk matters more than the box.

Exit ticket

• 1. No. Bending changes the shape, not the material.
• 2. The same thing. The pieces are smaller, but still the same material.
• 3. Any one of: bend, twist, stretch, break, fold, roll, squash.

Vocabulary

material = what a thing is made of; shape = the form of a thing; bend = make it curve; stretch = pull it longer; break = snap it into pieces; change back = return it to how it was.

Look for

Children who can say that the shape or size changed while the material stayed the same have met the heart of this topic.