[eratia]

Let them play. Sports is extracurricular anyways. Have good attendance and make good grades - Reward - PLAYING SPORTS

I think, like you, that sports are a privilidge, and should be restricted to those who do the things that allow them those privilidges. When they do those things and do them well, there will be no need for them to repeat a grade.

If they fail at academic tasks, or attendence issues, playing football wouldn't be a reward for them a second time through. I want every student to succeed, and I'm not against holdbacks as a whole, but rather holding back for sports sake. One year's enough for each grade level of athletic competition.