I was actually working on a longer comment that would've included a mention of scratch. Right now the focus is on the robotics competition, but in the spring that may be something I try to introduce them to. The problem will be access to computers. There just aren't enough available for the entire group (though attendance has dropped recently, so unfortunately there may be enough computers to handle all of them soon).
If it helps, chromebooks are nice little laptops that can be had for a couple hundred bucks. If you have monitors and keyboards a Raspberry Pi might work well as a computer and is about $50 with SD card, power supply, etc.
