I thing Bobert is probably right about this, but why has it come to this. I can recall trying to fill in for teachers--yes, I know, that's pretty pointless--but the curriculum had been dumbed down in high school to what I recalled covering in grade school. It seems to me that one of the by-products of the cultural revolution of the 1960's was the beginning of the push to teach to the "lowest common denominator," at which point everyone else in the class is bored. The first step in finding a solution is to identify the problem.