After much arguing with iMovie (suspect it was my fault) here is a short clip of an experiment we did last term.
Easy to replicate at home with an adult. You need a teabag that has a string that is stapled to it (I found Dilmah teabags work best).
Carefully remove the staple and tip the tea out. You should be left with a thin paper tube.
Stand the tube on its end and light the top. It will fall over in the slightest breeze (even if you pull away too quickly) so make sure you are somewhere sheltered.
Thanks to George our video expert. You probably don't want your volume up too loud but keep an eye on the faces in the background.