Wow that is a giant difference, especially in cognitive capacity. I.e. by 11 you should be able to understand more or less anything (i.e. including abstraction, recursion, e.t.c) ... but a 5 yo might just be comprehending the number-symbol/object-count correspondence.

you could try to approach with a single theme? I.e. I heard from talk by Felienne Hermans, that her code club used alot of sprites/images from the Donald Duck comics, as everybody was reading that, and then you could scale by ability?

I.e. younger kids could do just animations, older kids interactions?