Each school has their own AP and transfer credit policy. My D got 33 credits from AP when she enrolled CoE at UMich including US History. Some are useful for fulfilling pre-req courses, others for non-engineering elective requirements. At the end she took some more electives and made some of the credit useless. Otherwise, they are all useful in her case. If not, she would have dropped some of the AP credits within the first semester to avoid paying upperclassmen tuition earlier. Anyway, she started paying at upperclassmen rate after freshmen year.