Or https://www.arduboy.com/ https://www.arduboy.com/. (Though both of these are "more capable" in the sense of kids being able to make their own games for them;

Or https://www.arduboy.com/ https://www.arduboy.com/. (Though both of these are "more capable" in the sense of kids being able to make their own games for them; not necessarily in the sense of the games having even the fidelity of a Gameboy Color.)