Brian Greene (if you’ve watched any physics related science program on TV you’ve probably seen him) has launched World Science U
He has divided his free-of-charge WSU curriculum into three levels: quick, 30- to 90-second videos that explain a single narrow concept in physics (he has recorded a remarkable 500 of these); two- to three-week courses that involve no homework and—to the delight of more people than would admit it—no math; and longer, in-depth, college-level courses, stuffed with all of the equations it takes to master the material in a truly academic way. He also includes what he calls “Office Hours,” giving real students the opportunity to ask the virtual Greene any questions that come up in the course of a lecture. After 18 years of teaching, he knows what the most frequently asked of those questions are likely to be.
What I like about this approach is it allows you to access the primary resource (the videos) without having to drill down through the course. This makes it a useful resource for teachers.