Battery to USB Charger
I designed this little guy as an intro to soldering project for undergraduates. It's heavily inspired by the MintyBoost by Adafruit, primarily with just a few part changes to SMD instead of through hole. I also like to add as much visual documentation as possible, so the PCB has a schematic of a boost converter with relevant [high-level] design equations.
Sorry for the weird image, electronics are my thing. Pictures, not so much.
Documentation Files
I used EagleCAD to make this, nothing too special!