Math lesson plan Β· 7th grade (Year 8 in England) Β· 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 Β· 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 + (β5) > 0 β x > 5Prompt: Solve it like an equation.
- Solve: β4x > β32 β x < 8Prompt: Divide both sides by β4.
- Solve: x / (β7) < 0 β x > 0Prompt: Multiply both sides by β7.
Hook Β· 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 Β· 7 min
- Work through the example out loud, saying why you do each step, not just what you do.
- Example: Solve: 3x β 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 Β· 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: 8x β 6 > 66 β x > 9Prompt: Add 6 on both sides.
- Solve: β7x β 8 < β57 β x > 7Prompt: Add 8 on both sides.
You do: independent practice Β· 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 Β· 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 4(x β 2) β₯ 20? (9 / 5 / 6 / 3) β 9Prompt: Solve the inequality first.
- Solve: 5x β 15 β₯ 10 β x β₯ 5Prompt: Add 15 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