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 · 3rd grade (Year 4 in England) · 30 minutes

Planning a fair test

Working scientifically

CCSS NGSS.SEP 3CCSS NGSS.3-PS2-1England: KS2 Y3–Y4 Working scientifically

Objective and success criteria

Students will: Planning a fair test.

  • 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: Choosing a measuring tool

Leads to: Independent, dependent and control variables

Materials: Simple equipment for a fair test, Results table template, Mini whiteboards, A diagram or short video clip of the idea, Printed student sheet (below).

Warm-up · 4 min

  • Quick retrieval from earlier learning (Choosing a measuring tool). Students answer on mini whiteboards.
  • Show answers together and note who needs support in the main task.
  1. Which tool would you use to measure how long a candle burns? (a measuring jug or cylinder / a thermometer / a stopwatch or timer / a ruler or tape measure) → a stopwatch or timerPrompt: Is it a length, a temperature, a mass, a time or an amount of liquid?
  2. What could you measure with a ruler or tape measure? (how long a toy car takes to roll down a ramp / how much milk is in a glass / the mass of a pumpkin / how tall a sunflower has grown) → how tall a sunflower has grownPrompt: What does this tool measure: length, temperature, mass, time or volume?
  3. Kofi wants to find out which ball bounces highest. Which tool helps most? (a thermometer / a measuring jug / weighing scales / a metre stick (long ruler)) → a metre stick (long ruler)Prompt: Bounce height is a length.

Hook · 3 min

  • Show a simple experiment with one thing changed and ask what makes it a fair test.
  • Share the objective: Planning a fair test. 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: Leo tests which paper towel soaks up the most water. What should he change?
  • Step 1: He is testing types of paper towel, so that is the only thing he changes.
  • Step 2: So the answer is: the type of paper towel
  • Answer: the type of paper towel
  • 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. Priya tests which surface a toy car rolls furthest on. What must she keep the same? (the type of surface / nothing / how far the car rolls / the height of the ramp) → the height of the rampPrompt: Only the surface should change.
  2. Ben tests whether salt water or tap water freezes faster. Which must he keep the same? (the type of water / whether the water has salt / the time each one takes to freeze / the volume of water in each cup) → the volume of water in each cupPrompt: He is changing the type of water and measuring the time.

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. Fair tests: which statement is true? (If a result surprises you, you should hide it. / You should keep everything else the same. / One try is always enough. / A fair test means everyone gets a turn.) → You should keep everything else the same.Prompt: Think about what makes a test fair.
  2. Ben tests whether salt water or tap water freezes faster. Which must he keep the same? (the time each one takes to freeze / the type of water / the volume of water in each cup / whether the water has salt) → the volume of water in each cupPrompt: He is changing the type of water and measuring the time.

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: Choosing a measuring tool.
  • Use concrete materials: simple equipment for a fair test.
  • 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: Independent, dependent and control variables.
  • 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-3.

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

eurekami

Planning a fair test

Name

Date

Score/ 6

  1. Question 1

    Leo tests which paper towel soaks up the most water. What should he change?

    • A. the type of paper towel
    • B. the amount of water
    • C. the time he waits
    • D. the size of the towel

  2. Question 2

    Ben tests whether salt water or tap water freezes faster. Which must he keep the same?

    • A. the volume of water in each cup
    • B. whether the water has salt
    • C. the type of water
    • D. the time each one takes to freeze

  3. Question 3

    Fair tests: which statement is true?

    • A. If a result surprises you, you should hide it.
    • B. You should keep everything else the same.
    • C. One try is always enough.
    • D. A fair test means everyone gets a turn.

  4. Question 4

    Why is it a good idea to repeat a test several times?

    • A. To check the results are reliable
    • B. Because the first try never counts
    • C. To change the answer
    • D. To make the test unfair

  5. Question 5

    Omar tests how the length of a guitar string changes its note. He uses strings of different lengths. What else should stay the same?

    • A. nothing else matters
    • B. the note he hears
    • C. how tight and thick the strings are
    • D. the length of the strings

  6. Question 6

    Isla tests which ball bounces highest. She drops one ball from 1 m and another from 2 m. What is wrong?

    • A. She should use only one ball
    • B. Nothing, it is fair
    • C. She should not measure the bounce
    • D. The drop height should be the same

Free from eurekami.com

for the adult only

Answer key: Planning a fair test

  1. 1. A. the type of paper towel

  2. 2. A. the volume of water in each cup

  3. 3. B. You should keep everything else the same.

  4. 4. A. To check the results are reliable

  5. 5. C. how tight and thick the strings are

  6. 6. D. The drop height should be the same