I was unaware of this site until today, stumbled across it through the KET Encyclomedia info page here
If you scroll down, there is contact information for private and homeschools. I sent my email today and will update the info I get back asap. Love those KET/PBS resources.
Enjoy! (UPDATE: the info is on the site for pricing should be on the site, but for 12 months for a homeschool, the price was in the hundreds, so none for me thanks)