ComputerCraft turtles on modded minecraft. If you must spend money on hardware, buy them desktop upgrades, more memory or the fastest processor that'll fit in

ComputerCraft turtles on modded minecraft. If you must spend money on hardware, buy them desktop upgrades, more memory or the fastest processor that'll fit in the socket (may need to upgrade BIOS first...) or a top of the line graphics card. I think turtles are easy to program, they're in LUA and are a step above blockly type stuff. I kinda like the LUA APIs, they're not ridiculous or anything. They're simple enough that you'll get a chance to build useful larger functions / subroutines. At least its cheap. If they throw up their hands in frustration at programming their own tunnel mining program, at least you'll find out soon and it'll be cheap. Start with building a robot smart enough to build stairs all the way down to bedrock. Extend to have it place actual stair steps and torches for light, etc. Note that there's a subtle difference between a future-EE-teen who thinks programming robots is cool and a future-EE-teen who thinks robot hardware is cool (like motor H-bridges and gray code position encoders and sensors and generally melting solder). Obviously the latter is not going to find modded minecraft amusing. There is also the "competition robot" set which usually isn't programmable but amounts to homemade RC cars, you specifically don't want that, just mentioning it as something to look out for and avoid in the market.