I'm not a big fan of April Fools' Day. Why don't we change it to April Smart Person's Day? Maybe that doesn't have the same ring to it, but I like the idea much better.
The origin of April is unclear, although it is commonly thought that it has something to do with New Year's Day being moved from April 1 to January 1. Apparently, it took a while for people to catch on in the 16th century, so a lot of people didn't know right away. Those who didn't know were called fools, and people played practical jokes on them. Eventually these pranks became a tradition.
Now we have access to all the knowledge we need or want, so let's enjoy the day in a much more positive way. Be nice, and if you must play a joke on someone, make sure it doesn't do any damage.