He could also participate in top level youth ensembles outside of his school, if located in an urban area like NYC or San Francisco. For instance, top musical students at UC Berkeley and Stanford play in the San Francisco Symphony Youth Orchestra. He could also commute to an area for lessons, as well. Many students, not majoring in performance at their schools, commute to NYC to study with a top teacher - from Yale, Princeton, Vassar etc. He has a lot of different routes he could take. There are also threads on this forum discussing top orchestras.
http://talk.collegeconfidential.com/college-search-selection/1621956-universities-with-strong-orchestras-even-if-non-music-major-p1.html
http://talk.collegeconfidential.com/college-search-selection/1354916-what-colleges-have-the-best-orchestras-p1.html
http://talk.collegeconfidential.com/college-search-selection/1748416-what-colleges-have-good-music-orchestra-programs.html
(I find searching for “College Confidential” “music major forum” and then with keywords on google, an easier way to search than through CC.)