Deductive Proof: Reasoning from Theorems, Not Measuring: a week of ready-to-teach maths
Five days of lessons for Year 10 Space. Print this pack and the week is prepared.
Start here: five minutes to Monday
- Skim the week at a glance.
- Print the five days (plan + worksheet each).
- Cut out the card sheet once.
- Open the free interactive unit on your board.
- Teach from the plan.
The week at a glance
One lesson a day. Run them in order where you can.
| Day | Lesson | Children learn and do | On screen |
|---|---|---|---|
| 1 | Measuring shows one case; proving covers all | Practise the idea with talk, board and worksheet | Board: Measuring shows one case; proving covers all |
| 2 | A proof is a chain of justified steps | Practise the idea with talk, board and worksheet | Board: A proof is a chain of justified steps |
| 3 | Worked proof: vertically opposite angles | Practise the idea with talk, board and worksheet | Board: Worked proof: vertically opposite angles |
| 4 | Using a theorem to solve a spatial problem | Practise the idea with talk, board and worksheet | Board: Using a theorem to solve a spatial problem |
| 5 | One gap breaks the whole proof | Practise the idea with talk, board and worksheet | Board: One gap breaks the whole proof |
Materials
- This pack printed.
- Pencils and the board or projector.
- Optional counters or rulers if a day plan names them.
A note home
This week in maths we work on deductive proof: reasoning from theorems, not measuring. Ask: What did you practise today?
seegongsik.com/au/y10/space/AC9M10SP01/pack
Measuring shows one case; proving covers all
Children practise “Measuring shows one case; proving covers all” with talk, the board picture, and a short worksheet. About 40 minutes.
We are learning to
- explain measuring shows one case; proving covers all in Year 10 words,
- use the board picture to check thinking,
- record an example on paper.
Success criteria
- I can show one example of today’s idea.
- I can say the idea in a short sentence.
You need
- interactive unit open on “Measuring shows one case; proving covers all”,
- worksheet (next sheet), one per child,
Lesson flow (about 40 minutes)
| 5 min | Warm-up Ask: “What might help us today?” |
| 10 min | On the board Open “Measuring shows one case; proving covers all”. Ask: “What changed on the screen?” |
| 15 min | Worksheet Children complete the day sheet. |
| 10 min | Share Ask: “In one sentence, what was today’s idea?” |
Watch for
- Skipping the board -- bring them back to the picture.
- Correct answer with no explanation -- ask how do you know?
Answers and look-fors
- Meeting the idea sounds like a clear sentence about measuring shows one case; proving covers all.
Measuring shows one case; proving covers all
Use the board picture. Show your thinking.
A proof is a chain of justified steps
Children practise “A proof is a chain of justified steps” with talk, the board picture, and a short worksheet. About 40 minutes.
We are learning to
- explain a proof is a chain of justified steps in Year 10 words,
- use the board picture to check thinking,
- record an example on paper.
Success criteria
- I can show one example of today’s idea.
- I can say the idea in a short sentence.
You need
- interactive unit open on “A proof is a chain of justified steps”,
- worksheet (next sheet), one per child,
Lesson flow (about 40 minutes)
| 5 min | Warm-up Ask: “What might help us today?” |
| 10 min | On the board Open “A proof is a chain of justified steps”. Ask: “What changed on the screen?” |
| 15 min | Worksheet Children complete the day sheet. |
| 10 min | Share Ask: “In one sentence, what was today’s idea?” |
Watch for
- Skipping the board -- bring them back to the picture.
- Correct answer with no explanation -- ask how do you know?
Answers and look-fors
- Meeting the idea sounds like a clear sentence about a proof is a chain of justified steps.
A proof is a chain of justified steps
Use the board picture. Show your thinking.
Worked proof: vertically opposite angles
Children practise “Worked proof: vertically opposite angles” with talk, the board picture, and a short worksheet. About 40 minutes.
We are learning to
- explain worked proof: vertically opposite angles in Year 10 words,
- use the board picture to check thinking,
- record an example on paper.
Success criteria
- I can show one example of today’s idea.
- I can say the idea in a short sentence.
You need
- interactive unit open on “Worked proof: vertically opposite angles”,
- worksheet (next sheet), one per child,
Lesson flow (about 40 minutes)
| 5 min | Warm-up Ask: “What might help us today?” |
| 10 min | On the board Open “Worked proof: vertically opposite angles”. Ask: “What changed on the screen?” |
| 15 min | Worksheet Children complete the day sheet. |
| 10 min | Share Ask: “In one sentence, what was today’s idea?” |
Watch for
- Skipping the board -- bring them back to the picture.
- Correct answer with no explanation -- ask how do you know?
Answers and look-fors
- Meeting the idea sounds like a clear sentence about worked proof: vertically opposite angles.
Worked proof: vertically opposite angles
Use the board picture. Show your thinking.
Using a theorem to solve a spatial problem
Children practise “Using a theorem to solve a spatial problem” with talk, the board picture, and a short worksheet. About 40 minutes.
We are learning to
- explain using a theorem to solve a spatial problem in Year 10 words,
- use the board picture to check thinking,
- record an example on paper.
Success criteria
- I can show one example of today’s idea.
- I can say the idea in a short sentence.
You need
- interactive unit open on “Using a theorem to solve a spatial problem”,
- worksheet (next sheet), one per child,
Lesson flow (about 40 minutes)
| 5 min | Warm-up Ask: “What might help us today?” |
| 10 min | On the board Open “Using a theorem to solve a spatial problem”. Ask: “What changed on the screen?” |
| 15 min | Worksheet Children complete the day sheet. |
| 10 min | Share Ask: “In one sentence, what was today’s idea?” |
Watch for
- Skipping the board -- bring them back to the picture.
- Correct answer with no explanation -- ask how do you know?
Answers and look-fors
- Meeting the idea sounds like a clear sentence about using a theorem to solve a spatial problem.
Using a theorem to solve a spatial problem
Use the board picture. Show your thinking.
One gap breaks the whole proof
Children practise “One gap breaks the whole proof” with talk, the board picture, and a short worksheet. About 40 minutes.
We are learning to
- explain one gap breaks the whole proof in Year 10 words,
- use the board picture to check thinking,
- record an example on paper.
Success criteria
- I can show one example of today’s idea.
- I can say the idea in a short sentence.
You need
- interactive unit open on “One gap breaks the whole proof”,
- worksheet (next sheet), one per child,
Lesson flow (about 40 minutes)
| 5 min | Warm-up Ask: “What might help us today?” |
| 10 min | On the board Open “One gap breaks the whole proof”. Ask: “What changed on the screen?” |
| 15 min | Worksheet Children complete the day sheet. |
| 10 min | Share Ask: “In one sentence, what was today’s idea?” |
Watch for
- Skipping the board -- bring them back to the picture.
- Correct answer with no explanation -- ask how do you know?
Answers and look-fors
- Meeting the idea sounds like a clear sentence about one gap breaks the whole proof.
One gap breaks the whole proof
Use the board picture. Show your thinking.
Talk cards for Deductive Proof: Reasoning from Theorems, Not Measuring
Cut out. Hold up a card and give an example.
Give an example.
Give an example.
Give an example.
Give an example.
Give an example.
Store in an envelope labelled AC9M10SP01.
Show what you know: Deductive Proof: Reasoning from Theorems, Not Measuring
Work on your own. Use pictures or numbers.
Answers and look-fors
- Item 1 names the unit idea (deductive proof: reasoning from theorems, not measuring) in child words.
- Items 2-3: two different correct examples.
- Item 4: a real muddle for this topic.
Use day-plan look-fors across the week.