This is what the Church needs, from a Christian perspective.
The Ron Paul Curriculum is the best out there, but there is always room for improvement: a version built by and for Black America, or tied to UK history and culture, or with a more practical components & activities. (Keep the self-teaching style, though!)
The Robinson Curriculum is also good, but angled for a career in science.
And exactly when will we see good free online courses for Sunday school?
Or a good series of Christian theology courses online?