Pro-tip: consider starting college in the US, taking two semesters of German, and then doing this after your freshman year: http://culturalvistas.org/programs/abroad/congress-bundestag...
CBYX is a full year of free study and free living (replete with an allowance, free public transport, general coddling) in Germany, with the added bonus of being official guests of the German parliament. The only requirement is that you have a high school diploma and be between 18 and 24.
The program has a 'professional' focus, but when I did it most of us were still in college and returned to finish our degrees in the US. Back then that seemed very important, but today much less so and there's absolutely no reason why you couldn't participate in this program and then opt to stay in the German university system. Again, for free.