He is at it again, Lol. Free Tech4teachers has a free ebook download for you. It is called "The Super Book of Web Tools For Teachers." In this book (I just dl for review) there are a lot of resources noted and sites for free online curriculum and more. You definately want to check his post out. To dl the ebook you may need an account, but account is FREE.
courtesy post: http://www.freetech4teachers.com/