List of CS course offerings at various smaller colleges:
http://talk.collegeconfidential.com/discussion/comment/19190340/#Comment_19190340
With calculus 3, differential equations, and linear algebra completed while in high school, he may want to look for schools with graduate level offerings in math as well as a wider range of upper division math topics. Check course catalogs and faculty rosters. A few (but not that many) LACs, while undergraduate only, do include graduate level math courses in their offerings, since they expect some students to want them. But large math departments at research universities are likely to be easier to find a good selection of upper division and graduate math courses at.