Has he looked into the Congress-Bundestag exchange program? It is a terrific opportunity for those fluent in German. I have two friends who did the exchange on a gap year before attending Princeton and Davidson, and both loved it.
http://www.usagermanyscholarship.org/
Fortunately for your son, German isn’t exactly an obscure language. Even small colleges with very few language offerings typically offer German, so he has plenty of options beyond the most selective colleges. Begin with the usual considerations:
[ul][]How much can you afford? Will you need substantial financial and/or merit aid?
[]How big of a college is he looking for? Colleges range in size from places like the New College of Florida (860 undergrads) to Ohio State (46,000 undergrads).
[li] Is he looking for a particular setting (rural, suburban, college town, big city, etc.) and in a specific region(s) of the US?[/ul][/li]If he’s not sure yet what he wants in a college, I recommend visiting a variety of colleges in your area so he can figure out what environment suits him best.
Look into the test-optional and test-flexible colleges.
https://www.fairtest.org/university/optional
Some kids do better on the ACT. Has he done a practice test?