I want to develop a STEM kit featuring Botley the coding robot, but I'm not sure what other things to add that would make the kit complete.  Also, is there a better robot for young ones? 

For those of you with coding STEM kits, what did you include in the kits?  I'd like a Botley, a book, and something additional.

Ideas and experiences, please!

Thanks in advance,

Perri