Form 2 different teams and line them up.
The first person in line runs over to a pile of bubble gum, unwraps and chews a piece and as fast as they can blows a bubble. Once the judge has seen a real bubble, the next person in line does the same.
The first team to finish wins!
Historical fact:
Although chewing gum as been around since the time of ancient greece, it was in 1848 the John B Curtis made and sold the first commercial chewing gum. But it was in 1869 that William Finley Semphheld the first papent on chewing gum.
In 1928 Walter Diemer created "Bubble Gum" by accident while working on some different gum reciepes, he noticed that the gum ended up with bubbles.
