Maybe it's because you're targeting kids with your site, but i'm feeling a total sensory overload. The moving side bar is annoying to no end - for kids it's probably the next best thing behind chocolate cereal.
The main body is also a bit intense and the "nickelodeon" style logo could use some individuality as well. However, all this being said, this is coming from a domainer/evaluator that is heavily leaning towards clean cut, dark and glossy sites. For kids, your site is probably dead on - thus, Great Job!
The only thing that i'd suggest to really change is that the nav bar also gets some text description so the older kids that read the screen know where the navigation would lead.