My high school did the same dual-credit thing. I spent plenty of good money paying the (reduced) tuition for these college courses only to find that my university would not accept them since too many high schools were watering down the college courses that they offered.

As a more general comment, the point is that schools are forcing the lower achievers to be more equal to the higher achievers. Even though the higher achievers may be gaining ground, the lower ones are gaining it faster thanks to NCLB-esque policies. Thus we are just shrinking the standard deviation of academic achievement into singularity -- a point at which public academics become irrelevant because schools aren't making a lick of difference.