for kids.. there is time for everything. i would let them know of bitcoin in basic terms though a game, simple notions. the rest will do life and their natural curiosity
It is not necessary to teach kids about digital currencies even bitcoin, I mean let them experience the word without knowing this kind of things. Learning digital currencies means that they will be learning a lot especially in the side of the economy making their lives more serious and take their freedom as a innocent child. Let them know it in their own ways, we do not need to force them even if it is giving us good profit.