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.

Science lesson plan · 6th grade (Year 7 in England) · 30 minutes

Continuous and discontinuous variation

Cells, genetics and evolution

CCSS NGSS.MS-LS3-2CCSS NGSS.SEP 4England: KS3 Biology: Inheritance, chromosomes, DNA and genes

Objective and success criteria

Students will: Continuous and discontinuous variation.

  • 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: Inherited and environmental characteristics

Leads to: Use twins and clones to separate genes from environment

Materials: Microscope images or slides, Cell diagrams, Mini whiteboards, A diagram or short video clip of the idea, Printed student sheet (below).

Warm-up · 4 min

  • Quick retrieval from earlier learning (Inherited and environmental characteristics). Students answer on mini whiteboards.
  • Show answers together and note who needs support in the main task.
  1. Is this characteristic inherited or environmental: natural hair colour? (inherited (from parents) / environmental (from life)) → inherited (from parents)Prompt: Were you born with it, or did it happen during life?
  2. Identical twins have the same genes. One becomes much stronger. Why? (Strength is never affected by exercise. / Their genes changed into different ones. / The environment, such as exercise, made a difference. / They are not really twins.) → The environment, such as exercise, made a difference.Prompt: What can be different if their genes are the same?
  3. Inheritance: which statement is true? (The language you speak is inherited. / Some characteristics depend on both genes and environment. / If a parent loses a finger, its babies are born without that finger. / Children are always exact copies of one parent.) → Some characteristics depend on both genes and environment.Prompt: Which things can be passed on in genes?

Hook · 3 min

  • Show a microscope image of cells and ask what students think they are looking at.
  • Share the objective: Continuous and discontinuous variation. 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: Is this continuous or discontinuous variation: height?
  • Step 1: Continuous variation can take any value in a range, so it is measured.
  • Step 2: So the answer is: continuous
  • Answer: continuous
  • 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.
  1. Is this continuous or discontinuous variation: ABO blood group? (continuous / discontinuous) → discontinuousPrompt: Can it have any value, or only a few set categories?
  2. Five students measured their heights in cm: 184, 159, 167, 146, 150. What is the range of their heights, in cm? → 38 cmPrompt: The range shows how spread out the data are.

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.
  1. Five students measured their heights in cm: 176, 162, 155, 142, 172. What is the range of their heights, in cm? → 34 cmPrompt: The range shows how spread out the data are.
  2. A class records everyone's blood group. Which graph should they draw? (a bar chart with a separate bar for each group / a histogram with no gaps / a scatter graph / a line graph) → a bar chart with a separate bar for each groupPrompt: Blood groups are separate categories.

Watch out for

  • Everyday meanings of words getting in the way of the science meaning: define key words explicitly.
  • Remembering facts without the reason: ask "why?" and "what is the evidence?"

Support and stretch

Support

  • Review first: Inherited and environmental characteristics.
  • Use concrete materials: microscope images or slides.
  • 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: Use twins and clones to separate genes from environment.
  • 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/science/grade-6.

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

eurekami

Continuous and discontinuous variation

Name

Date

Score/ 6

  1. Question 1

    Is this continuous or discontinuous variation: pea seed shape (round or wrinkled)?

    • A. continuous
    • B. discontinuous

  2. Question 2

    Five students measured their heights in cm: 164, 157, 185, 173, 149. What is the range of their heights, in cm?

    Answercm

  3. Question 3

    A class records everyone's hand span in cm. Which graph should they draw?

    • A. a histogram with grouped ranges
    • B. a bar chart with gaps between categories
    • C. no graph is possible
    • D. a pie chart of names

  4. Question 4

    Is this continuous or discontinuous variation: body mass?

    • A. continuous
    • B. discontinuous

  5. Question 5

    Five students measured their heights in cm: 170, 143, 165, 183, 156. What is the range of their heights, in cm?

    Answercm

  6. Question 6

    Height data for a large group of adults usually form which shape when plotted?

    • A. two separate bars
    • B. a flat line
    • C. a straight rising line
    • D. a bell-shaped curve (normal distribution)

Free from eurekami.com

for the adult only

Answer key: Continuous and discontinuous variation

  1. 1. B. discontinuous

  2. 2. 36 cm

  3. 3. A. a histogram with grouped ranges

  4. 4. A. continuous

  5. 5. 40 cm

  6. 6. D. a bell-shaped curve (normal distribution)