Okay, I am probably an idiot because I really didn't see this coming at this point in time. In the back of my mind, I had a rosy picture of DS in a classroom setting again. Even during a recent Davidson seminar when Richard Rusczyk (AOPS)commented that DS was going to get bored in that geometry class and to be concerned with that class holding him back, I thought he was probably overly pessimistic since DS is a 6th grader and these are 8th grade GT kids. It wasn't that I didn't understand that DS would probably be ahead of most if not all the other students, but I never considered the teacher issue.
DS was quite excited to be in a math classroom after the last two years of working alone four days a week and a one-on-one teacher one day a week at school. However, his last two teachers had decades of experience teaching calculus and beyond and at least appeared to more than keep up with him IYKWIM so the issue of possible lower ability didn't concern me.
Unlike in elementary school, the middle school math teachers are supposed to be "highly qualified" with masters in the subject area. It is also possible that his teacher will turn out to be quite adequate at teaching the GT Geometry course. She is very nice and appears to handle the students well. However, I am somewhat disturbed at this point by several factors. First, I am tempted to ask the teacher (but don't want to be obnoxious) if she has ever taught Geometry because prior to this year the middle schools offered GT Algebra II rather than GT Geometry. Second, I am disappointed that DS not just outscored but outleveled her on the geometry reasoning assessment (Van Hiele) and I am disturbed that she told DS jokingly (he thinks)that she doesn't think she had anything to teach him. Third and I am being picky here, but I don't like the fact that DS sees that he always solves the problems faster than the teacher. On the one hand, it's great that she works some of the problems simultaneously with the students and maybe I am being unfair since DS is very fast and the only one who finishes ahead of her.
Needless to say, the course is moving very slowly for DS but it is early days yet and it wasn't like I expected the course to be exactly at his speed. I am really more disturbed by the factors I listed above. Other than keeping an eye on things, I am not sure that there is anything I can do or should do.