It's very simple to explain bitcoin to teenagers or children. As long as they are into playing computer games and other stuffs online. Tell them that bitcoin is one of the online money that they can use for converting it to cash. And when they heard about the "cash" thing for sure they can easily understand each detail with it.
It looks like it's a good idea, I'm sure when the children are playing games by collecting bitcoin then
automatically she will learn to know the bitcoin as means of payment more fast, practical and simple.
It's either you're being sarcastic or you're just plain dumb. How can playing games "automatically" teach the kids what bitcoin is? If they play games, they are just having more experience about the game. They are learning more about the game and nothing else unless the game is all about how to use bitcoins, and even then, the kids will not easily comprehend it.
You don't see someone playing GTA V on their computer saying "Oh, wow. I totally know how to drive a car." the same way you don't see someone playing games to earn bitcoins saying "Oh, wow. High score! Now I totally know how much transaction fee there is, how they are computed, and transaction is really fast even when you transact with somebody from across the globe."
Too long, didn't read: The games that pay bitcoins teach you nothing about bitcoin.