If they are less than 10yrs, look into Alice: http://www.alice.org/index.php http://www.alice.org/index.php. Teaches fundamental building blocks while they play

If they are less than 10yrs, look into Alice: http://www.alice.org/index.php http://www.alice.org/index.php. Teaches fundamental building blocks while they play with scene creation. Have used it for several classes and each one was outstanding. My favorite for older kids is to find an open-source video game with easily modifiable parameters, like lives, enemy count, sizes, etc., Start by asking them to change various things - class nearly runs on auto-pilot before too long.