I have a hamster in my classroom. They are very easy to care for. All pet supply stores will have hamster cages. I've gone through my share of them because hamsters are very smart and find their way out if they really want to. Make sure there is enough room in the cage for them to play. I just checked the Target website and they have cages listed, if you have a Target near you, you can check there. Boy hamsters, like most male creatures, have 2 little sacks.
However, if they are very young, the sacks won't be showing yet.
How did your kids just "come home" with 2 hamsters today?