This is a great site with a lot of hardware lessons based on using Arduinos mostly.
A collection of Arduino activities and documents for beginners
Free circuit design Web app.
Here are some of the most compelling features:
- Virtual breadboard based design, allowing to build and experiment with circuits just as you would in real life.
- You can add an Arduino to your design, and edit the code right in your browser.
- Real-time and interactive simulation of both your Arduino code and the circuit attached to it.
- Full collaborative editing (think of Google Docs for electronics).
- Powerful yet easy component editor, making it super easy to add new components to the shared library.
A large and growing list of resources for teaching students about electronics and Arduinos
It has been reported that this book has been used by seventh graders!
This little booklet, written by Prof. Jan Borchers, introduces you to using an Arduino. It covers the latest beginner-friendly board, the Arduino Uno R3, and the latest version of the Arduino IDE, 1.0.3. It comes with shopping tips and a SparkFun online wish list to get the parts you’ll need.
Very nice set of lessons for beginners. Has text and also videos.