Give him a year or two to explore adulthood without having classes. This may help him find what he's interested in. I wanted to be a scientist my entire life, but I got to college and I just couldn't get the grades. I spent the next year just taking every 101 class in every subject until I found something I could get good grades in. Turns out it was writing. So I was an English major. I ended up working in the software Industry, anyway.