Math lesson plan · 1st grade (Year 2 in England) · 30 minutes
Make a sensible estimate
Number sense
CCSS 1.NBT.A.1England: Y2 Number and place value
Objective and success criteria
Students will: Make a sensible estimate.
- 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: Count to 100 by ones and tens
Leads to: the next skill in this area.
Materials: Place value chart, Base-ten blocks or a number line, Mini whiteboards and pens, Printed student sheet (below).
Warm-up · 4 min
- Quick retrieval from earlier learning (Count to 100 by ones and tens). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- Count by tens. What is missing? 30, __, 50, 60, 70 → 40Prompt: Each number is 10 more than the one before.
- Count by tens. What is missing? 60, 70, __, 90, 100 → 80Prompt: Each number is 10 more than the one before.
- Count by tens. What is missing? 10, __, 30, 40, 50 → 20Prompt: Each number is 10 more than the one before.
Hook · 3 min
- Show a number in the news or a price tag and ask what each digit is worth.
- Share the objective: Make a sensible estimate. 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: Without counting one by one, which is the best estimate for the number of hearts? ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥ ♥
- Step 1: There are 52, which is close to 50.
- Step 2: About 50.
- Answer: about 50
- 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.
- Without counting one by one, which is the best estimate for the number of diamonds? ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ (about 10 / about 50 / about 20 / about 5) → about 50Prompt: Each full line has 10.
- Which is the most sensible estimate for the number of pages in a picture book? (1000 / 30 / 300 / 3) → 30Prompt: Picture it in your head.
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.
- Without counting one by one, which is the best estimate for the number of diamonds? ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ ◆ (about 10 / about 20 / about 100 / about 50) → about 50Prompt: Each full line has 10.
- Which is the most sensible estimate for the number of apples in a small bag? (600 / 1 / 6 / 60) → 6Prompt: Picture it in your head.
Watch out for
- Reading 1,045 as one thousand four hundred five: point to each place and say its value.
- Thinking a longer number is always bigger, even with decimals (0.45 vs 0.5).
Support and stretch
Support
- Review first: Count to 100 by ones and tens.
- Use concrete materials: place value chart.
- 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-1.
Free lesson plan from eurekami.com/lesson-plan-builder