Kids can be taught about bitcoins with reference to gold as how we buy gold and store it and sell when prices are high. This should work for the trading aspect, while using bitcoins as online money can be taught much easily because kids today are very much into technology and internet. They can understand the concept of Digital money quite easily because they are still in learning stage and thus will grasp easily.
I think trading and investing is a serious thing and should not be learn by kids because they are still young and their interest is not yet on serious things. They can be taught but the question is, will their interest will remain in bitcoin?
In my opinion, it is really a good idea to tell our kids about this concept of crypto currency and bitcoin. It is not necessary to tell them all the complex things related to bitcoin, but we can give them a basic introduction about bitcoin. This will help them in knowing well about bitcoin. We can teach them using visual assistance as kids learn more things by looking at the things instead of telling them verbally.