I was thinking today about CLEP exams that I took way back in 1968 in Western Civ, Modern European History, and American Government for a total of 18 semester hours. CLEP was brand new and nobody knew the level of difficulty they would be. There were no sample questions or study guides back then. I was interested to see that CLEPs still exist: https://clep.collegeboard.org/exam $80 an exam. Back then, a B&M college would grant you credit for CLEP units without charge. I dunno if that's still the case. The TV ad I saw for CLEPs showed Ab Lincoln interviewing for a job. When he was asked about college, he said he had not gone but he read a lot on his own. All the while he was fingering his stovepipe hat nervously.
Ummm . . . you may have noticed that we have an entire forum dedicated to discussing CLEP and similar tests. CLEP, DANTES, and Other Exams for Credit