After MHacks I went back to high school and started an EECS club. Lots of people have been saying that they are getting marked absent even though they are attending the club. I wanted to create a solution so that everyone wouldn't get marked absent, and a solution so that I don't need to take attendance. Many people in the EECS club have iPhones, and I had never written an iPhone app, so I figured that now would be a good time to try. To keep track of everyone in the classroom I created 2 apps: one for their phones, and one for my iPad. The iPad app connects to the phones via bluetooth and lets them know that they are present at class, from there they can send that data to the school office to be marked as present.
I got a lot of help from PJ Loury, a mentor from Jawbone.