Activity steps

1. Conduct this experiment in an area free from flammable materials and resources (e.g. curtains). Inside on an open kitchen bench is ideal. Make sure there is no breeze, including heaters or fans or your rocket may not launch.
2. Take your tea bag and carefully remove the staple. Try not to rip the bag.
3. Tip out the tea leaves onto the plate and flatten them out.
4. Open-up the tea bag and manipulate it to form a cylinder shape.
5. Stand the tea bag upright like a column on the plate and on top of the tea leaves. This will be your launchpad.
6. ADULTS TO DO- have little fingers and people stand back at a safe distance. Now use your lighter or matches and light the top of your cylinder. You can encourage your child to count down the blast off whilst you do this. For example “3,2,1 blast off!”
7. Stand back and watch your tea bag rocket launch into the air and float back down. Be patient… the rocket will not fly upwards straight away!

Questions to ask before/during the experiment:

• What do you think will happen when I light the tea bag?
• What do/did you notice?
• Why did you think the tea bag was able to fly to the sky?
• What do you know about rockets?
• What happens to hot air?

How the tea bag rocket works…

When you light the top of the teabag, the fire heats up the air molecules inside the tea bag cylinder and causes them to become energized and move around quickly. The air molecules spread out and the air become less dense.  

As the tea bag burns the tea bag turns to smoke and ash. The smoke lifts and the ash remains. The rocket (remaining ash) rises once it become light enough for the hot air to force upwards. The ash is light, and hot air rises, so it doesn’t take much force to send the ash flying high into the sky.   

Variations:

• Try using different tea bags- why do you think they did/didn’t they work?
• Perhaps you could try making a tissue paper cylinder to launch. Does it work?
• Would this work with normal paper?