B.B.
I used to teach at a daycare, and this is very common. Some kids really do get so wrapped up in what they're doing, that they don't think to stop and go to the restroom. It could also be that since he's new, he doesn't feel comfortable enough to tell someone he doesn't know that he needs to go. They should have regular potty times, but that may be up to 2 hours apart (should not be more than this). Talk to the teachers about asking him more often, at least until he's more comfortable.