Online Classes for Students and Teachers
First, if your child does best when moving through a subject at their own pace, at a time when they choose, on a topic they select, you must take a look at The Khan Academy. It is relatively new, started in 2009, and exists online only. For a broader description of it, reviews, and the ideas behind it, read this article. This is the sort of thing you could point your child too and they might just run with it. You won't have any worries about what they are doing online all that time.
Stanford University hosts and online High School for students all over the world.
The single best place to start for teachers and students looking for online education classes and tools is Edutopia. Take a look and browse around. It was set up but the producer of the Star Wars films.
There are lots of online resources for gifted high school students.
Online Classes for Adults and Advanced High School Students
If you are not trying to get academic credit, the most incredible source of absolutely riveting talks by remarkable people is TED.com, a site that offers the best of the TED Conference lectures.
If you are seeking academic credit the State University of New York has hundreds of degree progams and thousands of courses online.
MIT has about 1900 online courses. Yale 200. University of California has 200. Stanford has entire online professional degree programs. Harvard offers about 100 open admissions courses online.
Apple has started up iTunesU which now hosts tons of free lectures from places like Stanford, MIT, and many other universities.
This guide to online schools and courses is pretty complete.
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