I have been teaching woodworking to a group of middle school kids for a couple of hours a week for the past 8 weeks. We built a book rack, a desk clock, wooden pens, and a bowling game in that time. I have now been asked to do an advanced class and I'm at a complete loss for ideas of what to do next. The sessions are 2 hours, 1 day a week for 8 weeks so we have 16 hours of instruction. The other constraint is that materials need to cost under $25/kid.
Anybody have any ideas of some projects that kids would like that would teach them some advanced skills? They are already proficient on all of the machines, so I'm thinking it's more about joinery techniques or something like that. Help!