Balloons disappeared into beacons filled with liquid nitrogen only to create liquid oxygen and ice inside of them "out of thin air" - literally! The liquid oxygen, released from the balloon, then rolled over the floor in little balls, in a levitating manner that looked quite alien. Liquid oxygen - and nitrogen - expand by about a thousand times into their gaseous state once you let them out of the genie bottle - which is why the kids were told that you couldn't drink it or you would explode. Nicely demonstrated by trying to keep the liquid nitrogen inside a bottle with a cork that flew half way to China after only a few seconds. Lots of shrieking from the huddling little lady scientists.
Then an extinguished match burst into flame while being submerged into a freezing liquid. Many bets were lost, because it happened to be liquid oxygen - a royal feast for the match. When a boy's hair was given the volume we all crave, by loading him up with electrons from a big silver ball, and he then proceeded to light a light bulb with his bare hands - the excitement was complete. Even I became enthusiastic, although it had been a very, very long day. All it took was was 12000 volts and several deadly, steaming fluids, completely alien to our planet. I don't ask much.
Well, all it really took was the enthusiastic little scientist I followed around for two hours.