If you haven't seen it, check out the Khan Academy (www.khanacademy.org).  It's a new non-profit online learning initiative with some very helpful videos and interactive lessons explaining various topics in math, science and some other fields. It represents an innovative and effective approach to online teaching and learning and at a very affordable price for the learner...free!   It started largely as a labor of love by Salman Khan for his cousin, I believe, who needed some tutoring in mathematics.  Khan began by tutoring her online in math using Yahoo's Doodle notepad.  Now he's gotten a multimillion dollar grant from the Gates Foundation.  The videos are free and on YouTube, too.  Khan holds three degrees from MIT and an MBA from Harvard.  He's a very smart guy and obviously dedicated to service as well.