Math lesson plan · 2nd grade (Year 3 in England) · 30 minutes
How much longer? Compare two lengths
Measurement
CCSS 2.MD.A.4England: Y2 Measurement
Objective and success criteria
Students will: How much longer? Compare two lengths.
- 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: Measure in cm, m, inches and feet; Subtract two-digit numbers with regrouping
Leads to: Length story problems
Materials: Rulers, scales and measuring jugs, Clock faces, Conversion chart, Mini whiteboards and pens, Printed student sheet (below).
Warm-up · 4 min
- Quick retrieval from earlier learning (Measure in cm, m, inches and feet; Subtract two-digit numbers with regrouping). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- What is the best estimate for the length of a bus? (120 m / 12 m / 12 cm / 1200 m) → 12 mPrompt: A centimetre is about the width of a finger nail.
- What is the best estimate for the length of a book? (250 cm / 25 m / 2500 cm / 25 cm) → 25 cmPrompt: A centimetre is about the width of a finger nail.
- What is the best estimate for the length of a finger nail? (1 m / 1 cm / 10 cm / 100 cm) → 1 cmPrompt: A centimetre is about the width of a finger nail.
Hook · 3 min
- Ask the class to estimate the length of the room or the weight of a bag before measuring it.
- Share the objective: How much longer? Compare two lengths. 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: Ethan's paper plane flew 40 cm. Tariq's flew 29 cm. How much further did Ethan's plane fly?
- Step 1: 40 − 29 = 11
- Step 2: 11 cm
- Answer: 11
- 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.
- Elena's paper plane flew 92 cm. Liam's flew 78 cm. How much further did Elena's plane fly? → 14Prompt: 'How much further' means find the difference.
- Sam's paper plane flew 46 cm. Elena's flew 18 cm. How much further did Sam's plane fly? → 28Prompt: 'How much further' means find the difference.
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.
- Ines's paper plane flew 69 cm. Ethan's flew 14 cm. How much further did Ines's plane fly? → 55Prompt: 'How much further' means find the difference.
- Maya's paper plane flew 69 cm. Zoe's flew 60 cm. How much further did Maya's plane fly? → 9Prompt: 'How much further' means find the difference.
Watch out for
- Measuring from the end of the ruler instead of zero.
- Converting units the wrong way (multiplying instead of dividing).
Support and stretch
Support
- Review first: Measure in cm, m, inches and feet.
- Use concrete materials: rulers, scales and measuring jugs.
- Give the first step of each question, or a partly worked example to finish.
- Pair with a confident partner for the guided practice.
Stretch
- Move on to: Length story problems.
- 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