TryRuby.org is an intermediate - advanced tool that helps you learn the programming language Ruby. Useful for developing mobile tools and other web 2.0 products!
The Computer Science Teachers Association is a membership organization that supports and promotes the teaching of computer science and other computing disciplines.
This is a fee based resource created by a Texas computer science teacher. It includes an entire computer science curriculum, and is aligned to the AP Computer Science exam.
This computational thinking curriculum, provided by Google, is intended to integrate computer science into math and science courses. The lessons teach computer science using Pyhon.
This British website provides a dozen or more lessons for computer science and related concepts. It is not a complete curriculum by any means, but lessons could be used in conjunction with other resources.
This is MIT's Open Courseware course Introduction to Python. It includes exercises and labs, and also links to the PDF textbook, "How to think like a computer scientist."
Wingware's Python IDE is an Integrated Development Environment designed specifically for the Python programming language. Product has a free trial and then user must purchase license.
Xcode is Apple's powerful integrated development environment for creating great apps for Mac, iPhone, and iPad. Xcode includes the Instruments analysis tool, iOS Simulator, and the latest Mac OS X and iOS SDKs.
Program by Design is an innovative project for computing education that combines motivation with principles. On the surface we use engaging contexts-our "hello world" program is an animation, and students have the opportunity to program games, mashups, phones, etc.-while teaching a principled and scalable approach to computing.