Alan Kay gives a great TED Talk about teaching or rather giving children the chance to find things out by themselves.
The whole talk is 20 Minutes. The really geeky and fascinating part starts at 12 Minutes, where he demos a software from the 100$-Laptop "One Laptop Per Child".
If you want to try it yourself, there is good news: The software is called Etoys and you can get it at http://www.squeakland.org. It is free, open source software, that runs on Windows, Linux and Mac.