Lots of college kids huff nitrous oxide for fun. They call this huffing gas or huffing whippets. Whippets are a favorite among the college and Grateful Dead crowd, but there are other things that people huff, like gasoline and white out. Especially white out among middle school kids. The kid who will sniff white out is probably the same kid who used to eat paste. This is what we refer to as stupid and dumb. Most college kids get into it because they feel like they are not really doing drugs. This is dangerous stuff. They have seizures and die from lack of oxygen to their brain, something that they don't seem to be using at the moment anyways. My advice is to stay away from the stuff.
This of course isn't to say that you should fear the dentist, who also uses this substance, but when I heard my friend had done it. I was upset.