http://www.exploringcs.org/wp-content/uploads/2010/08/ExploringComputerScience-v4.0.pdf
Incredible new version of this resource, all 296 pages of it. Has lots of lessons and activities.
I really like the Computer Intelligence lesson on page 73. It has a good list of chatterbots.
It has a big section on Scratch programming.
Another big section on robots with NXTs. There is a nice subsection on What is a Robot that I like. It starts on page 256. The activities include RoboCub, RoboDance, rescue robot and Tic-Tac-Toe!