Year 5 · Autumn 1.1 · Step 3

Earth & Space

Plan — parachute experiment

Planning a fair test to answer: does the size of a parachute change how long it takes to fall?

Arrival Starter I do We do Independent Exit ticket

🌱 Seedling · Working towards 🌿 Sapling · Expected 🌳 Oak · Greater depth

⏱ Whole lesson ≈ 44 min · pick a tier in the bar, or leave on "All"

Arrival 4 min

Recap of last lesson: air resistance.

Recap: air resistance

🌱 Seedling

Working towards

Finish: A bigger surface catches ____ air, so it falls ____.

🌿 Sapling

Expected

Air resistance is a type of what?
What two things affect its size?

🌳 Oak

Greater depth

If we wanted to test whether a bigger parachute falls slower, what would we need to be careful about?

Bridge into todayOver the next three lessons we run a fair test. Today we plan it — and meet variables for the first time.

Starter 5 min

Pose the enquiry question and gather predictions.

Our enquiry question

Does the size of a parachute affect the time it takes to fall to the ground? To answer it fairly, we change one thing and keep everything else the same.

🌱 Seedling

Working towards

Predict: bigger parachute → falls ____ (faster / slower).

🌿 Sapling

Expected

Make a prediction and give a reason using air resistance.

🌳 Oak

Greater depth

What would make the test unfair? List things we must keep the same.

I do · 1 6 min

Teacher models. Watch, then name the three variable types.

Independent, dependent, controlled

▶ Can't see it? Watch "Variables: independent, dependent and controlled" on YouTube

Swap the clip: change the ID after /embed/ (now J9kCgWAuB0Y).

Say thisThe independent variable is the one thing we change. The dependent variable is what we measure. The controlled variables are everything we keep the same to make it fair.

🔧

Independentwhat we change

📏

Dependentwhat we measure

🔒

Controlledkept the same

We do · 1 6 min

Apply the three types to our parachute test together.

Plan our parachute test

Change: parachute size | Measure: time to fall | Keep same: height, weight, material, string

Equipment & why

3+ parachute sizes · a stopwatch (time in parts of a second) · the same weight · the same drop height.

Only the size changes — that is what makes it a fair test.

I do · 2 4 min

Play the animation. Bust the classic mix-up between the variable types.

One change, one measure, rest the same

Change one thing (size), measure one thing (time), keep everything else the same.

Model the ruleIf we changed two things at once — say size and height — we would not know which one caused the difference. That is why only the independent variable changes.

Watch for: mixing up which variable is which. Repeat "change one, measure one, keep the rest the same".

We do · 2 5 min

Fire quick items and label them together.

Which variable is it?

Decide together

"The size of the parachute" → ? "The time it takes to fall" → ? "The height we drop from" → ?

Independent (change), dependent (measure) or controlled (keep the same)?

Independent 10 min

On your own. Sort each part of our plan, then write at your tier.

Variable sorter

🔧 Independent (change)

📏 Dependent (measure)

🔒 Controlled (keep same)

Tap a card to sort it…

🌱 Seedling

Working towards

Sort the cards. Then finish: We change the ____ and measure the ____.

🌿 Sapling

Expected

Sort them, then write our plan in one sentence: "We will change… measure… and keep the same…"

🌳 Oak

Greater depth

Explain why changing only one variable makes the test fair, and why our results could be trusted.

Exit ticket 4 min

Answer at your tier, then hand it in.

Show what you know

🌱 Seedling

Working towards

The variable we change is the ____ variable.
The variable we measure is the ____ variable.

🌿 Sapling

Expected

Name one controlled variable in our test.
Why must we keep them the same?

🌳 Oak

Greater depth

Write our prediction and explain it using surface area and air resistance.