I've kept or bred hamsters, rats, mice, gerbils, guinea pigs, rabbits and chinchillas. Unless your son is absolutely determined he only wants a hamster I'd try to guide him toward something less inclined to bite like a rat or guinea pig. All the hamsters I've had were more sensitive to rough handling than other animals, miniature Houdini's (escape artists) and also took more work to keep them clean. Guinea pigs are the least likely to bite, do take a little effort to keep clean, are not known as escape artists, will squeal in delight when you walk in the room once they get to know you but can be a little boring for some people. Chinchillas are usually very expensive and some states require a permit to keep them (not sure why, they aren't dangerous) so I wouldn't recommend them for a child but they are easy to tame and can be very interesting, not to mention looking very much like Pikachu except for the color. Rabbits are great pets once they get used to being handled and can with some training learn to use a litter box if kept in the house. Rabbits can also tend to become territorial and this could cause a conflict with other pets like cats and dogs. Mice are escape artists but easy to feed, very inexpensive and don't tend to bite as much as hamsters. Rats are my favorite of all - smart, easy to care for, very friendly (love to be carried around and cuddled once they get used to a person), inexpensive and they can also learn to do simple tricks. They are also either considered very cool or very gross by friends but are never boring. Gerbils are easy to care for and become somewhat friendly. They tend to be much "drier" than other small pets so it is rare that a gerbil's home will develop an odor. If you do purchase a hamster or other equally small mammal please do not keep it in a small wire cage. Some of them are sensitive to drafts, urine causes rust, and tiny legs and heads have been known to get stuck or injured between bars. Also avoid using pine or cedar shavings which are known to cause respiratory problems from the aromatic oils in the wood.
I totally agree with arach... Hamsters seem to want to bite everyone. I have had one nice one when I was younger, out of quite a few. I have had them chew there water bottle til it leaked, and everything else. I wouldn't own one again.
One the other hand, I have had great exper. with mice and rats. They are lovable, and trainable. I had Phantom(mouse) for almost 2 1/2 yrs. a really good life. She used to sit on my shoulder and squeek in my ear all the time. my mom hated it when I first got her, but she got used to the idea when she saw how tame and wonderful Phantom was. I would walk all around the house with her on my shoulder. She was great. Neither smell as bad as everyone says if you keep the cages clean.
I had a client who had guinea pigs. They were great for her kids. Both kids loved them to death. They were friendly and had great personalities. They would bring them to our grooming shop to have the toenails trimed. She had them for I think 5 or so yrs. She lost them both to cancer.
Check your local shelter, sometimes I find guinea pigs at my shelter. If it was me, I would get him a baby rat and enjoy the fun. good luck with what ever you decide
I would try to steer him toward a rat. They are surprisingly intelligent and have lots more personality than hamsters.
However, knowing that he has made up his mind -- Hamsters are solitary animals and can be VERY territorial. They might have a bunch of them living together at the pet store, but they're babies. I've read that you should NEVER get two of them -- especially two females. I don't have personal experience with that, but it sounds like it could have tragic consequences.
The last two hamsters we've had in our house had fairly short lives. One of them was not accustomed to handling, so she bit often.