Elastic Energy Launcher

Alex

Mission Briefing.

Alex has challenged Professor Picklebottom to build a launcher without batteries, motors or electricity. The only materials he can use are paddle pop sticks, elastic bands and tape.

Can you help Alex build an Elastic Energy Launcher and discover how engineers store and release energy to make things move?

7-12 yrs

15 min

Medium

Stage 2, Stage 3

Designed by Darin Carr (BSc, DipEd)
NESA Accredited Teacher · Chemistry & Physics Specialist · 30+ years in-class teaching
Creator of the LAB™ Learning System
Last updated: June 2026 ·

[Cite this resource ↗]

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Elastic Energy Launcher

NESA Accredited Teacher
High school chemistry & physics specialist 30+ years
The Crazy Scientist in primary schools — 15 years

International conference presenter on science education
Creator of the LAB™ Learning System
Curriculum aligned: NSW Science & Technology K–6 (2024)

[Copyright Notice]

A picture is worth a thousand words — check this out and see if you can spot the science hiding in plain sight.

Mission Equipment

• 19 paddle pop sticks

• 8–10 elastic bands

• Sticky tape

• Scissors

• Pencil

Let’s Investigate

1

Gather Your Materials

Collect all the materials needed to build your launcher.

3

Build the Frame

Join the side supports together with cross bars to create a sturdy launcher frame.
Wrap the elastic band around the corss bar and then loop it under to the other side of the strut and hook it onto the paddle pop stck to secure it to the side strut.

5

Attach the Launch Arm

Stretch the elastic band from the launch arm around the first crossbar.
Place the band into the grooves at the ends of the side struts.

The launch arm should now be able to pivot and spring forward.

7

Attach button to trigger

Cut a small piece of a paddle pop stick.
Tape it over the pencil mark.
This small block becomes the trigger stop.

When pressed, it releases the launch arm.

2

Build the Side Supports

Cut ~ 1 cm off the ends of three sticks.
Two will be used for the side struts.

4

Build the Launch Arm

Tape one end of the launch arm using the third shorter stick.
Tape the end as shown so the rubber band hangs from its end.

6

Create the Trigger

While holding it in the firing position:
Use a pencil to mark where the trigger will be placed.
You may need a partner to help.

8

press trigger

Use a small piece of a paddle pop stick that you cut before.
Tape it over the pencil mark.
This small block becomes the trigger stop.

Did it work? Share the science! Tag @the_crazy_scientist on Instagram — we love seeing your experiments!

The Crazy Scientist LAB Learning System™

Every experiment follows The Crazy Scientist Lab Learning System™ — a simple way to help kids think like real scientists.

LINK to what they already know,
ACTIVATE curiosity through hands-on discovery
BUILD understanding that actually sticks.

Have you ever stretched an elastic band and let it go?

Maybe you’ve launched one across a room, fired one from your fingers, or watched a slingshot send an object flying.

In every case, the elastic band started still. Yet somehow it was able to make another object move.

How does a stretched elastic band transfer energy to something else?

Think back to what happened when you pressed the trigger.

Where was the energy stored before the car moved?
What had to happen for that energy to reach the car?
Which part of your launcher do you think did the most important job?

Elastic potential energy converts to kinetic energy — that's how all launchers work.

A longbow stores energy in bent wood. What releases it?
A mousetrap snaps shut instantly. Where was the energy stored just before?
A trebuchet flings a boulder using a falling weight — how is that similar to your launcher?

"Want the full teacher guide? The Crazy Scientist Lab includes classroom delivery tips, how to manage the WOW moment, differentiation for Stage 2 & 3, — ready to teach tomorrow."

Think Like a Scientist

Scientists don't just do ONE experiment; they change one part of the experiment (independent variable) and then see how it affects another part of the experiment

(dependent variable)

Change ONE variable and test again.

What happens if you add a second elastic band?

What happens if you make the launch arm longer or shorter?

🧪 Try it! Change ONE thing and test again. What did you discover?

Dr Puddledrip’s Science Tip

Want to go deeper? Tap a section below to explore. ▼

The Science Behind It

What’s Really Happening?

Your Elastic Energy Launcher doesn’t need batteries, electricity or a motor.

Instead, it stores energy inside stretched elastic bands.

The paddle pop stick frame acts like the skeleton of the launcher. It keeps everything aligned so the stored energy can be directed where it’s needed.

When the trigger is released, the elastic bands pull the launch arm forward. The launch arm transfers energy into the toy car, causing it to move.

Engineers use this same idea whenever they need to store and release energy. Catapults, slingshots, bows and many mechanical launch systems all rely on energy transfer.

You may have already explored energy transfer in experiments such as the Balloon Rocket Blast-Off, where stored energy in a stretched balloon pushes a rocket forward, or the Ghost Glider, where careful design helps control how energy is used during flight.

The better your launcher’s frame, launch arm, and trigger work together, the more efficiently energy can be transferred into the car.

Ready for a Bigger Challenge?

Building the launcher is only the first step.

Scientists often use engineering designs as tools for investigations.

Can a heavier car travel further?

Does adding more elastic bands increase the distance?

Is there an ideal launch arm length?

Inside The Crazy Scientist LAB, you’ll find extra Engineering Missions and Investigation Challenges that help you test, improve and redesign your launcher like a real engineer.