Yes, try it both ways. With him as a dependent, you should be eligible for the same $2500 turion credit. So, all things equal, the family should come out $500 ahead if you claim him as a dependent.
Normally a student-dependent, under 24, is not eligible for the full tuition credit. If the student actually has a tax liability, there is a provision to allow him to claim a non-refundable tuition credit. But then the parent must forgo claiming the student as a dependent, and the $500 other dependent credit. The student must still indicate that he can be claimed as a dependent, on his return. This is worth up to $2500 (AOTC shifts to all non refundable).
He's not old enough for the Earned Income Credit.
