UVA website says as below. They are not as specific as some other colleges about years required, but “the best program available in core subjects” - where they expressly include foreign language in core - can easily be understood to mean 4 years, assuming that is offered by the school. I think only taking 2 years FL (not even 3) to be able to take band (and not clear which others you mean - are they also non-core) is going to be a disadvantage. How much of a disadvantage depends on other things too, though I would strongly, strongly suggest he take at least 3 years FL. Has he taken 4 years of all the other cores? How will your son compare to other applicants from his high school? What other colleges is he applying to?
### 1. Take the best program available to you in your core subjects.
Make sure that your class schedule demonstrates that you are taking advantage of all that your school offers. Talk to your counselor and parents to help determine the right program for you. Colleges will want to see that you are pursuing a strong schedule, but they will also want to see good grades.
What do we mean by the core subjects? Those are English, math, foreign language, social studies, and science.