In your app manager, look for a menu button and see if it gives you the option to view system apps.
But this still may not solve your problem. Unless you have the tablet locked down with parental controls, he could easily install third party camera apps. Messaging apps, such as SMS, Facebook, and even Chrome itself (via website upload options) can still have access to the camera. If you're not wanting him to have any access to the camera whatsoever, about the only way to ensure that is to physically disable the hardware. Unless you're technically inclined, you may want to take it to a shop and see if they can unplug or otherwise disable the camera module.