Math lesson plan · 6th grade (Year 7 in England) · 45 minutes
Write inequalities for real-life limits
Algebra
CCSS 6.EE.B.8England: KS3 Algebra
Objective and success criteria
Students will: Write inequalities for real-life limits.
- 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: Inequalities: meaning and solutions
Leads to: Match inequalities and number-line graphs
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 (Inequalities: meaning and solutions). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- Which inequality matches? "You must be at least 17 years old to ride." (x is the amount) (x > 17 / x < 17 / x ≥ 17 / x ≤ 17) → x ≥ 17Prompt: 'At least' means that number or more.
- Which inequality matches? "You must be at least 9 years old to ride." (x is the amount) (x > 9 / x < 9 / x ≥ 9 / x ≤ 9) → x ≥ 9Prompt: 'At least' means that number or more.
- Which inequality matches? "More than 17 people came to the concert." (x is the amount) (x > 17 / x < 17 / x ≥ 17 / x ≤ 17) → x > 17Prompt: 'At least' means that number or more.
Hook · 5 min
- Show a "think of a number" puzzle and ask the class to work out the starting number.
- Share the objective: Write inequalities for real-life limits. 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: Write an inequality: The speed limit is 88 km/h (s = speed). (Type ≤ as <= and ≥ as >= if you need to.)
- Step 1: s ≤ 88
- Answer: s ≤ 88
- 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.
- Write an inequality: You must be at least 23 years old to join the climbing wall (a = age). (Type ≤ as <= and ≥ as >= if you need to.) → a ≥ 23Prompt: “At least” means ≥; “at most” means ≤.
- Write as an inequality: x is greater than 2. → x > 2Prompt: Start with x, then the sign, then the number.
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.
- Write an inequality: A phone needs at least 27% charge for an update (c = charge). (Type ≤ as <= and ≥ as >= if you need to.) → c ≥ 27Prompt: “At least” means ≥; “at most” means ≤.
- Which inequality matches: You need more than 17 points to win a prize (n = points). (n < 17 / n > 17 / n ≥ 17 / n ≤ 17) → n > 17Prompt: Is 17 itself allowed?
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: Inequalities: meaning and solutions.
- 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: Match inequalities and number-line graphs.
- 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-6.
Free lesson plan from eurekami.com/lesson-plan-builder