I have been very involved with FIRST LEGO League (FLL) for many years. I started as a coach, then did some special projects for the organization, and now act as a mentor for coaches around the country. This year I took on a local team to help them implement an invention they dreamed up as part of the research project they do besides building their robot.
They came up with a retrofit sytem for a car to prevent death by carbon monoxide poisoning. Now most teams would present a paper design to the judges, these kids wanted a working system. So for the last few weeks, I have spent the weekends teacing them the basics of electronics and programing something other then their LEGO robots. We picked the Arduino for the simplicity and available support materials. We also picked the MQ series sensors (available at Sparkfun) as the gas sensor.
Last night they got it all to work mounted to the display board they made. The end to end test works great. Blow the monoxide (or in our case for safety reasons a substitute) into the sensor and all manners of LEDs and horns start to blare. For my sanity, I convinced them to add a silence switch during development so as not to have to wait for the sensor to clear and reset the system.
This coming weekend the team is off to their local competition. If they do well enough, they get invited to the New Hampshire State tournament. I have my fingers crossed for them.
And now I can get back to my own projects as my shop was overun with team materials.