Math lesson plan · 2nd grade (Year 3 in England) · 30 minutes
Identify a shape from clues about sides, corners and equal sides
Geometry
CCSS 2.G.A.1England: Y2 GeometryEngland: Y3 Geometry
Objective and success criteria
Students will: Identify a shape from clues about sides, corners and equal sides.
- I can answer questions on today's skill on my own, without help.
- I can explain each step and say why it works.
- I can check my answer and spot a mistake.
Before and after
Needs first: Polygons: sides and vertices; Shape riddles: sides, corners and curves
Leads to: the next skill in this area.
Materials: Rulers and protractors, Squared or dotted paper, Shape cut-outs, Mini whiteboards and pens, Printed student sheet (below).
Warm-up · 4 min
- Quick retrieval from earlier learning (Polygons: sides and vertices; Shape riddles: sides, corners and curves). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- I am round. I have no sides and no corners. What am I? (triangle / hexagon / circle / square) → circlePrompt: Draw the shape the clues describe.
- How many sides do a octagon and a pentagon have altogether? → 13Prompt: How many sides does a octagon have?
- I have 3 straight sides and 3 corners. What am I? (hexagon / triangle / circle / rectangle) → trianglePrompt: Draw the shape the clues describe.
Hook · 3 min
- Show a photo of a building, a tile pattern or a road sign and ask what shapes and angles students can spot.
- Share the objective: Identify a shape from clues about sides, corners and equal sides. Read the success criteria together.
I do: model it · 7 min
- Work through the example out loud, saying why you do each step, not just what you do.
- Example: I have the fewest sides a straight-sided shape can have. What am I?
- Step 1: Triangle
- Answer: triangle
- Pause after each step and ask a student to say what comes next.
We do: guided practice · 6 min
- Do these together. Students try each step on whiteboards before you reveal it.
- Use the hints as prompts rather than giving the answer.
- I have 4 square corners and all my sides are the same length. What am I? (square / rectangle / pentagon / octagon) → squarePrompt: Sketch a shape that matches every clue.
- A shape has 3 straight sides. How many corners does it have? → 3Prompt: Draw a few shapes and count both.
You do: independent practice · 7 min
- Students work on the student sheet. Circulate and check the first two answers of every student early.
- Students who finish: write a question of their own for a partner, with the answer.
The 6 questions are on the student sheet below, with answers in the key.
Exit ticket · 3 min
- Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.
- I have 8 straight sides. Some road signs have my shape. What am I? (pentagon / octagon / square / triangle) → octagonPrompt: Sketch a shape that matches every clue.
- A closed shape has 3 corners and only straight sides. How many sides does it have? → 3Prompt: Draw a few shapes and count both.
Watch out for
- Thinking a square turned on its corner is no longer a square.
- Reading the wrong scale on a protractor.
Support and stretch
Support
- Review first: Polygons: sides and vertices.
- Use concrete materials: rulers and protractors.
- Give the first step of each question, or a partly worked example to finish.
- Pair with a confident partner for the guided practice.
Stretch
- Explain a common mistake in writing and how to fix it.
- Write a word problem that uses today's skill, then solve a partner's.
Homework and more practice
Free online practice with hints and printable worksheets for this skill: eurekami.com/math/grade-2.
Free lesson plan from eurekami.com/lesson-plan-builder