Comment Re:Radical thought here (Score 4, Informative) 307
Stanford had a good approach to this, at least when I went there (probably still do).
The intro-CS courses were offered in two parts (CS106A/B) or a single accelerated course (CS106X), with the requirement that students taking the accelerated course have previous programming experience.
All students end up covering the same material (which is important, since high school instruction varies greatly in quality), but you don't have half the class getting bored and the other half lost at the same time.