Gifted students often are underserved in middle schools but that is less a problem in high schools. In most high schools, there are the normal track and the honor track. The honor track consists the honor/AP classes (or pre-IB/IB classes if offered). If your kid stays with honor/AP classes, then he should be properly challenged.
IB and AP classes are roughly comparable in the eye of colleges. We did some research on IB vs AP issue before my kids enter high school. In the end, we choose a school with AP program for some other reasons. IB with its international root is an excellent choice if your kids intend to study abroad. But it is less known to US colleges. Ivies know IB well and so do large public universities such as UCs. The problem is with middle-tire colleges. You need to check the college's IB policy. They are all different.
Although they are different, you kid can be successful with either one of them.
