I'm really happy with this little drone, the Eachine H8. If you play video games, it's super quick to learn how to control it, and it's very resistant to crashes.

... and now I learn that I can hack the firmware! so for an "affordable programmable drone suitable for children", I think that's the best answer (it's just $14 on banggood). Buy spare batteries though, and maybe with budget < $100, buy two of them :)