Lesson plan · Ages 7–10 · 30 min
Lesson plan: what makes a rocket fly?
A ready-to-teach 30-minute session on thrust, weight and why rockets carry oxygen. Needs one balloon and no preparation.
Objective: children can explain that a rocket goes up because it pushes gas down, and that it must carry its own oxygen because there is none in space.
- Starter (5 min) — Blow up a balloon and let it go. Ask: what made it fly? Collect answers without correcting them yet.
- Teach (8 min) — The air rushes out one way, so the balloon goes the other way. A rocket does the same, but with burning gas instead of air. Open the Push & Go book on the website and read the first three pages together.
- Practice (10 min) — Weight versus thrust. A Falcon 9 weighs 549,000 kg. Its engines push with 7,600 kN. Ask what would happen if the push were smaller than the weight. (It would sit there.) Use the Rocket Lab and remove engines until it fails to lift off.
- Twist (5 min) — Ask: could you light a candle in space? Establish that fire needs oxygen and space has none, so a rocket carries a whole tank of it.
- Plenary (2 min) — Each child says one thing a rocket needs. Collect: fuel, oxygen, push, something to push against — nothing.
1. What does a rocket push against to go up?
2. Why can a rocket work in space but an aeroplane cannot?
You need: one balloon. Optional: a screen for the Rocket Lab. Nothing else, and nothing to print in advance.
For the grown-up
- The most common wrong answer in the starter is "the air pushed against the room". Do not rush to correct it — the twist at the end does the work, because a rocket has nothing to push against and works anyway.
- If asked why rockets are pointy: it is only for the air on the way up. In space the shape does not matter at all.
- Follow-on worksheet: "Why is a rocket almost all fuel?" continues directly from the weight-versus-thrust section.
Every number on this sheet comes from: Falcon 9 Block 5 — specifications · Merlin rocket engine family