Tea bag experience Maths class

We started of by taking the tea leaves out of the teabag and then Mrs stone opened the teabag and put it on the chair.After Mrs stone put it on the chair she grabbed the lighter and put it on fire while our maths class watched. 

The air inside the teabag was hotter than the cold air outside.The cold air is more "dense" this means the particles are closer together and they have less energy than hot air.This meant that the teabag flew up in the air.