balloon powered,  Mars Phoenix Lander
Two of my students and I have been selected through the PSIP (Phoenix Student Interns Program) organization to work with a NASA scientist on the Phoenix mission to Mars.  Phoenix is a lander that  touched down in the Martian arctic on May, 25th 2008.  It was designed to analyze samples of Martian permafrost to determine if this environment is or was capable of supporting life.   As a part of the deal, I do some educational outreach for the mission so I decided to design a little model of the lander that kids could build.  
I've made two versions of the model.   Both versions  fly under balloon power.  Version 1 is a little more elaborate and a little harder to put together.  Version 2 is simpler and easier to put together and fly.  See my YouTube  video of the  model here.  One of the mission controllers at JPL apparently downloaded and made one of these models.  Here is a picture of it on his console taken from the video feed during landing.  Learn more about the mission by visiting this site.

Phoenix Mockup
On the day of the landing, I had a little show at The Crucible to commerate the event.  I built a semi-scale (about 90% of the actual size) mockup of  the lander in its landing configuration.  Here are some pics of the mockup.

Phoenix  Lander Game
One of my PSIP students made this little lander game. (zip file)

Etch-A-Sketch Projectile Motion
This is a program I wrote that illustrates the principles of projectile motion using an Etch-A-Sketch metaphor.

West Coast Plate Tectonics
This is a program I wrote that illustrates the spreading ridges, transverse fault and subduction zone that characterize the tectonics of the California coast.  (zip file)

Rocket Altitude
Here is a little graphical rocket altitude calculator I made.  
(zip file)