On the original question:
DD's district has an optional full time program for gifted kids in middle school. Once identified students are eligible to attend a designated middle school with gifted core classes (math, social studies, science and english) and general population electives (foreign language, PE, music, art, drama....). Students are tested and placed for math. Since the district has a high cut off ( about 2-4% of kids in this socio/econ advantaged group) the district increases student numbers by concentrating the kids in one school. Out of district students can also test in on a space available basis. They are expanding to a second middle school. This works well since the gifted kids make up about 15% of the school population and thus provides a solid peer group. I think this option works well for gifted kids; I'm not sure how well it works for mid to upper level kids. In high school there seems to be more differentiation available for every level.
