Sorry, I realize that "you can't use a Chromebook as an external monitor/keyboard" was an oversimplification and VNC is an option. I should have clarified that we are a virtual organization (we're a website with free educational materials but we don't do in-person programs). The options you mentioned are generally feasible for situations where you have knowledgeable on-site staff to do the initial setup, and you're right, once it's set up it's not too hard to use - but doing all the initial setup is a complete non-starter for families/teachers with zero experience. We also do already have more advanced content for both Arduino and Raspberry Pi - so the question here is more about finding the lowest possible barrier to entry way to blink that first LED.