We moved our 9th graders to the abandoned middle school next door several years ago and it's been an incredible success. It's a good transition year, they're able to bond with their peers and their teachers (most of whom teach exclusively at that building, some of whom teach at both campuses), and they're still able to try out for competitive teams on the Main campus.

No real obstacles that I know of. It sucks (as a coach) not to know the freshmen very well (but you tend to hear about the most talented ones).

I teach 10th grade, too, and the sophomores are well adjusted by the time they arrive at the Main building. They've made regular visits to the other campus during that freshmen year, they've had daily "Advisory" periods run by Senior leaders, and they're still included in big events like pep rallies and dances.

Hope that helps. I'm fully in favor of it.