Internet of Things (IoT)
My son and I finished assembling our Million Color Flashlight http://makezine.com/projects/million-color-hsl-flashlight/ on Friday night, so I was cleaning up my workshop last night and decided to assemble something I had lying around. I've been sponsoring different kickstarter projects for Arduino-based products and a kit I had in my shop was for the RasPiO Duino, an Arduino prototyping board you program by attaching it directly to the GPIO pins on a Raspberry Pi.
Here it is all assembled, it was fun to practice my soldering skills:
I think this would be an excellent addition to any elementary or middle school class on microcontrollers. It allows someone to learn how to program the Arduino with limited computer hardware (just a $35US Raspberry Pi, keyboard, mouse and monitor). I'm going to see if I can come up with an interesting project for this thing soon.