Math lesson plan · 2nd grade (Year 3 in England) · 45 minutes
Show length sums and differences on a number line
Measurement
CCSS 2.MD.B.6England: Y2 Measurement
Objective and success criteria
Students will: Show length sums and differences on a number line.
- 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: Length story problems; Find numbers on a number line to 100
Leads to: the next skill in this area.
Materials: Rulers, scales and measuring jugs, Clock faces, Conversion chart, Mini whiteboards and pens, Printed student sheet (below).
Warm-up · 5 min
- Quick retrieval from earlier learning (Length story problems; Find numbers on a number line to 100). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- Omar joins a 47 cm strip of paper and a 42 cm strip end to end. How long is the new strip? → 89Prompt: End to end means add the lengths.
- Amara has a 87 cm piece of string and cuts off 67 cm. How long is the piece that is left? → 20Prompt: Cutting off takes length away.
- Jamal joins a 41 cm strip of paper and a 14 cm strip end to end. How long is the new strip? → 55Prompt: End to end means add the lengths.
Hook · 5 min
- Ask the class to estimate the length of the room or the weight of a bag before measuring it.
- Share the objective: Show length sums and differences on a number line. Read the success criteria together.
I do: model it · 10 min
- Work through the example out loud, saying why you do each step, not just what you do.
- Model one question from the student sheet, thinking aloud.
- Pause after each step and ask a student to say what comes next.
We do: guided practice · 10 min
- Do these together. Students try each step on whiteboards before you reveal it.
- Use the hints as prompts rather than giving the answer.
You do: independent practice · 10 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 8 questions are on the student sheet below, with answers in the key.
Exit ticket · 5 min
- Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.
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: Length story problems.
- 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
- 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