Consider some of the strong Midwest flagship U’s. They tend to have highly ranked math, computer science and chemistry majors, among others. It can be possible to get first class lab/research experience, take grad level classes and plenty of other field electives. U of Illinois is mentioned above- U of Wisconsin in in the same ballpark but has a nicer campus (ask the many from Illinois who prefer OOS tuition to their own good flagship). Historically it was the state flagships of the Midwest that developed strong CS departments- at a time the east coast didn’t have the major (go waay back to the 1960’s- UW had a CS building).
Your son needs a strong school that fits his academic ability and offers strong departments in STEM fields. Having a good math background is useful for computer science (and going beyond cross listed courses). Once he is in college your son will refine his path.