NCAA is the kind of college gymnastics you see on TV. There are club leagues such as NAIGC and informal arrangements between schools that are more recreational and allow all levels to participate (assuming the school maintains a club team). Although the NCAA code differs somewhat from the the USAG JO level 10 code, the overall minimum difficulty requirements are pretty similar. D1 will be mostly former elites, level 10s and some stronger level 9s (there are many D1 schools and depending on their recruiting level will have various combinations of the above). D3 schools aren't generally as competitive, but I'd say the minimum skill level is comparable to level 9.