Math lesson plan · 2nd grade (Year 3 in England) · 45 minutes
Find the rule of a number pattern
Algebra
CCSS 2.NBT.A.2CCSS 2.OA.C.4England: Y2 Number and place valueEngland: Y3 Number and place value
Objective and success criteria
Students will: Find the rule of a number pattern.
- 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: Growing patterns: the same amount added each step; Skip count by 5s, 10s and 100s from any number
Leads to: Missing numbers in patterns that go up or down
Materials: Balance scales or a balance drawing, Algebra tiles, Function machine cards, Mini whiteboards and pens, Printed student sheet (below).
Warm-up · 5 min
- Quick retrieval from earlier learning (Growing patterns: the same amount added each step; Skip count by 5s, 10s and 100s from any number). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- Count in hundreds: 289, 389, 489, __, 689 → 589Prompt: Only the hundreds digit changes.
- What number comes next? 7, 12, 17, 22, __ → 27Prompt: How much bigger is each number than the one before?
- Count in hundreds: 239, 339, 439, 539, __ → 639Prompt: Only the hundreds digit changes.
Hook · 5 min
- Show a "think of a number" puzzle and ask the class to work out the starting number.
- Share the objective: Find the rule of a number pattern. 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.
- Example: What is the rule? 13, 113, 213, 313
- Step 1: 113 + 100 = 213
- Step 2: +100
- Answer: +100
- 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.
- What is the rule? 21, 18, 15, 12 (+3 / −3 / −2 / −4) → −3Prompt: Is the pattern going up or down?
- The pattern is 38, 138, 238, 338, … What is the 6th number? → 538Prompt: Find the rule first.
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.
- What is the rule? 40, 50, 60, 70 (+9 / +11 / −10 / +10) → +10Prompt: Is the pattern going up or down?
- The pattern is 32, 27, 22, 17, … What is the 6th number? → 7Prompt: Find the rule first.
Watch out for
- Doing an operation to one side of an equation but not the other.
- Reading 3x as 3 + x, or thinking x always stands for one particular number.
Support and stretch
Support
- Review first: Growing patterns: the same amount added each step.
- Use concrete materials: balance scales or a balance drawing.
- 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: Missing numbers in patterns that go up or down.
- 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