I completely agree with Karen, a guinea pig could be a great classroom pet!

Try looking at cavyspirit.com about caring for them. I have a guinea pig (as seen in my icon) named Taffy. He is the sweetest thing. He doesn't bite at all and loves to be scratched behind the ears.

If you do get a guinea pig as a classroom pet try adopting. Like puppy mills, there are backyard guinea pig breeders. I didn't know that when I got taffy (I was only 5 or 6) and most guinea pigs coming from petstores have health problems. Taffy had lice when we brought him home.

If you have any questions on the general care of guinea pigs feel free to PM me. I love bragging about my baby and how well mannered he is!

BTW, an older guinea pig might be better for a class room pet since they are less skittish and more friendly. Boars (the males) are more outgoing and don't gets scared as easily as the sows. But the downside is they don't have very long life spans. normally around 6-8 years with good care. (Taffy is 7)