Science lesson plan · 5th grade (Year 6 in England) · 45 minutes
Independent, dependent and control variables
Working scientifically
CCSS NGSS.SEP 3CCSS NGSS.MS-PS2-2England: KS2 Y5–Y6 Working scientificallyEngland: KS3 Working scientifically
Objective and success criteria
Students will: Independent, dependent and control variables.
- 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: Planning a fair test
Leads to: Drawing conclusions from evidence; Evaluating experiments (research summaries)
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 · 5 min
- Quick retrieval from earlier learning (Planning a fair test). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- Why is it a good idea to repeat a test several times? (To check the results are reliable / Because the first try never counts / To change the answer / To make the test unfair) → To check the results are reliablePrompt: What if one result was a mistake?
- Which question can be answered with a fair test? (Who is the best scientist? / Is a rainbow beautiful? / Does a heavier parachute fall faster? / What is your favourite plant?) → Does a heavier parachute fall faster?Prompt: A fair test changes one thing and measures another.
- Fair tests: which statement is true? (Repeating a test helps you check your results. / One try is always enough. / You should change as many things as possible. / If a result surprises you, you should hide it.) → Repeating a test helps you check your results.Prompt: Think about what makes a test fair.
Hook · 5 min
- Show a simple experiment with one thing changed and ask what makes it a fair test.
- Share the objective: Independent, dependent and control variables. 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: Investigation: Does the surface area of a puddle affect how fast it evaporates? Which is the independent variable (the one you change)?
- Step 1: Change: surface area of the water. Measure: time for the water to evaporate. Keep the same: volume of water, temperature of the room.
- Step 2: So the answer is: surface area of the water
- Answer: surface area of the water
- 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.
- Investigation: Does the number of cells (batteries) affect how bright a bulb is? Which is the independent variable (the one you change)? (number of cells / height of the ramp / length of wire / brightness of the bulb) → number of cellsPrompt: Independent variable: the one you change. Dependent variable: the one you measure.
- Investigation: Does the surface area of a puddle affect how fast it evaporates? Which is the dependent variable (the one you measure)? (heart rate (beats per minute) / volume of water / surface area of the water / time for the water to evaporate) → time for the water to evaporatePrompt: Independent variable: the one you change. Dependent variable: the one you measure.
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.
- Investigation: Does the temperature of water affect how quickly sugar dissolves? Which is the independent variable (the one you change)? (water temperature / mass of sugar / time for the sugar to dissolve / minutes of exercise) → water temperaturePrompt: Independent variable: the one you change. Dependent variable: the one you measure.
- Investigation: Does the size of a parachute affect how long it takes to fall? Which is a control variable (one you keep the same)? (distance the car travels / size of the parachute / drop height / time to fall) → drop heightPrompt: Independent variable: the one you change. Dependent variable: the one you measure.
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: Planning a fair test.
- 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: Drawing conclusions from evidence; Evaluating experiments (research summaries).
- 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-5.
Free lesson plan from eurekami.com/lesson-plan-builder