Agree with pp’s that Northeastern would be a high reach, and Oberlin would be a reach as well.
One thing I just wanted to ask if 1) if you son qualifies for any accommodations for taking standardized tests (such as extra time), and 2) if he used them when he took the pre-ACT? If he does qualify for extra time (or anything else) and he didn’t use them for the pre-ACT, his test scores could be dramatically different with accommodations. It would be very worthwhile to explore him getting accommodations and taking advantage of them. Also, have him try taking both tests (again with accommodations if he qualifies). Some students are naturally better at one than the other.
I’ll recommend that following schools, some of which have already been mentioned here:
Wheaton
Skidmore
Union
St. Lawrence
Bard
Bennington (this school is tiny, though)