Code.org
A non-profit with a vision that every student in every school should have the opportunity to learn computer programming.
Codecademy
Teach yourself to code, interactively, for free!
Coder Dojo
An open source volunteer coding club
CodeSchool
Teaches web technologies with video lessons, coding challenges, and screencasts.
Learn Python the Hard Way, 3rd edition (not really!)
Access the free HTML version of the book.
Learn | Code
More resources for Hour of Code
Python Introduction
An introduction from Google
Teach Yourself to Code
Teaching Your Kids How to Write Computer Programs
An article by Marshall Brain
Udacity
Introduction to Computer Science from Stanford University’s free courseware “Udacity”