Is there any way I can set the drive letter for either my USB drive or my iPod? I would like to make them always have the same letter on every computer I use. I can change them at home where I have administrator rights but on every computer I use at school it changes (sometimes the E, F, or G drive, but not always the same).

I doubt that is possible since you are not administrator of the other computers.

As jholland said, if you don't have admin priveleges, then no, you can't change it.