The reasons for repeating are many --obviously. The classic rationale is the more mercenary, sports. I feel that this is somewhat out of control but on the other hand it is usually boys. In our public school there was a real problem with girls getting much higher grades than boys in everything. They tend to behave better, have better speaking and writing skills and so on. I actually think it is a huge problem in education. (In fact given the state of our inner cities I think later start times (sleep) and changing the age kids start school would have significant benefits for boys across the board but there are the teachers unions to contend with but I digress) If one is a motivated parent (with resources) one can help these boys with weaker executive function and other issues through tutors, support and the ultimate advocacy-private school. In conclusion, I think boys benefit in many many ways. My youngest started private school in Kindergarten in NYC and thus was a little older so we felt there was no reason to repeat but he is in BS now with many boys in his grade that are repeating the grade.