@leifhammer@ASECS@histodons@Chanders two possible strands - the learner centred curriculum centred stuff mentioned above. But you might also want to glance at the history of intelligence and the idea that there are different kinds of intelligence people are born with (which will fit them for studying different stuff) - probably fair to start with Thurstone. Also, a warning - this was a very eugenicist, racist era in education/psychology.