I'd like to do a kid's CNC workshop, planning way ahead - can you help?

[Ray Doeksen]

I'm looking for a few people for NEXT year's Chicago Student Invention Convention that could explain to kids (K-8) about how CNC tools are built and how they work and could help me prepare for a workshop/demo where we help the kids put together a kit that controls one stepper motor with a programmable thingamajigger of some kind and then we play with some code for the rest of the session and the kids get some experience writing code that moves a thing they built, however simple. I'm thinking just a dial-type readout on the end of a stepper motor, to familiarize them without getting bogged down in the problems of a more practical machine. If you can help me plan that out, I'd appreciate the help and you can either participate in the workshop with the kids, or not, as your time and whim dictate.