Math lesson plan · 7th grade (Year 8 in England) · 30 minutes
Solve two-step inequalities
Algebra
CCSS 7.EE.B.4.BEngland: KS3 AlgebraEngland: GCSE Foundation Algebra
Objective and success criteria
Students will: Solve two-step inequalities.
- 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: Solve one-step inequalities, including dividing by a negative
Leads to: Solve inequality problems about budgets and limits
Materials: Balance scales or a balance drawing, Algebra tiles, Function machine cards, Mini whiteboards and pens, Printed student sheet (below).
Warm-up · 4 min
- Quick retrieval from earlier learning (Solve one-step inequalities, including dividing by a negative). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- Solve: x + 10 < 23 → x < 13Prompt: Solve it like an equation.
- Solve: −8x ≤ −56 → x ≥ 7Prompt: Divide both sides by −8.
- Solve: x / (−3) ≤ −2 → x ≥ 6Prompt: Multiply both sides by −3.
Hook · 3 min
- Show a "think of a number" puzzle and ask the class to work out the starting number.
- Share the objective: Solve two-step inequalities. 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: Solve: 3x − 6 < 3
- Step 1: 3x < 9
- Step 2: x < 3
- Answer: x < 3
- 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.
- Solve: 9x − 3 ≥ 24 → x ≥ 3Prompt: Add 3 on both sides.
- Solve: −3x − 9 < 9 → x > −6Prompt: Add 9 on both sides.
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.
- Which value of x satisfies 5(x − 2) ≥ 20? (5 / 4 / 2 / 6) → 6Prompt: Solve the inequality first.
- Solve: −5x + 2 ≥ 7 → x ≤ −1Prompt: Subtract 2 on both sides.
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: Solve one-step inequalities, including dividing by a negative.
- 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: Solve inequality problems about budgets and limits.
- 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-7.
Free lesson plan from eurekami.com/lesson-plan-builder