Back to the lesson plan builder
Lesson length30 min45 min60 min
Questions🔀 New questions

Print the plan for yourself; the student sheet prints on its own page after it.

Math lesson plan · 8th grade (Year 9 in England) · 45 minutes

Slope (gradient) of a line

Algebra

CCSS 8.EE.B.5CCSS 8.EE.B.6CCSS 8.F.B.4England: KS3 AlgebraEngland: GCSE Foundation Algebra

Objective and success criteria

Students will: Slope (gradient) of a line.

  • 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: Coordinates in all four quadrants; Proportional relationships; Equivalent fractions

Leads to: Scatter graphs and correlation; Graphs of linear equations y = mx + b; Find the slope from a graph using rise over run

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 (Coordinates in all four quadrants; Proportional relationships; Equivalent fractions). Students answer on mini whiteboards.
  • Show answers together and note who needs support in the main task.
  1. Is this relationship proportional? x: 5, 7, 8 → y: 15, 22, 24 (Yes, proportional / No, not proportional) → No, not proportionalPrompt: Find y ÷ x for each pair.
  2. Is this relationship proportional? x: 3, 7, 10 → y: 6, 15, 20 (Yes, proportional / No, not proportional) → No, not proportionalPrompt: Find y ÷ x for each pair.
  3. Is this relationship proportional? x: 2, 4, 7 → y: 16, 33, 56 (Yes, proportional / No, not proportional) → No, not proportionalPrompt: Find y ÷ x for each pair.

Hook · 5 min

  • Show a "think of a number" puzzle and ask the class to work out the starting number.
  • Share the objective: Slope (gradient) of a line. 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.
  • Model one question from the student sheet, thinking aloud.
  • 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.

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.

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: Coordinates in all four quadrants.
  • 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: Scatter graphs and correlation; Graphs of linear equations y = mx + b; Find the slope from a graph using rise over run.
  • 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-8.

Free lesson plan from eurekami.com/lesson-plan-builder

eurekami

Slope (gradient) of a line

Name

Date

Score/ 8

  1. Question 1

    Find the slope (gradient) of the line through (4, 2) and (9, −5). Give a whole number or a fraction in simplest form.

    xy−12−6612−12−66120AB

    Answer(as a fraction)

  2. Question 2

    The line passes through the two marked points (0, 0) and (2, −6). What is its slope?

    xy−66−12−66120y = −3xAB

    Answer

  3. Question 3

    Daniel cycles at a steady speed. The graph of distance (km) against time (hours) passes through (0, 0) and (4, 20). What is the slope, and so the speed in km/h?

    xy123456789101530450y = 5x(4, 20)

    Answer

  4. Question 4

    Find the slope (gradient) of the line through (−1, 1) and (4, 2). Give a whole number or a fraction in simplest form.

    xy−12−6612−12−66120AB

    Answer(as a fraction)

  5. Question 5

    The line passes through the two marked points (0, −3) and (2, −7). What is its slope?

    xy−66−12−66120y = −2x − 3AB

    Answer

  6. Question 6

    Zoe cycles at a steady speed. The graph of distance (km) against time (hours) passes through (0, 0) and (5, 55). What is the slope, and so the speed in km/h?

    xy12345678910660y = 11x(5, 55)

    Answer

  7. Question 7

    Find the slope (gradient) of the line through (−2, 4) and (−4, −3). Give a whole number or a fraction in simplest form.

    xy−12−6612−12−66120AB

    Answer(as a fraction)

  8. Question 8

    The line passes through the two marked points (0, 3) and (2, −3). What is its slope?

    xy−66−12−66120y = −3x + 3AB

    Answer

Free from eurekami.com

for the adult only

Answer key: Slope (gradient) of a line

  1. 1. -7/5

  2. 2. -3

  3. 3. 5

  4. 4. 1/5

  5. 5. -2

  6. 6. 11

  7. 7. 7/2

  8. 8. -3