Make it Relevant (Score 1)

You can try to ask students what they want to do - but most teenagers dont have a clue. But find out what they are into - what games they play, what topics they spend their time interested in and develop activities around those. It helps to have some ideas in mind. Here are a few possibilities

1. Games, everyone likes games. You can recreate simple videogames (most kids today have never played asteroids - its a not too hard game to make).
2. Use sensors and robotics to get the computer to interact with the rest of the world (e.g. have the computer respond to people walking by). Scratch and Kinect is a great tool for this.
3. Create something useful - find a need in their house or school and figure out how to solve it. Kids (especially girls) like to be helpful. The Hacking for good meetups have been pretty successful.