Bitcoin is difficult to explain. I also felt difficulties in understanding bitcoin for the firs time. Let's share how to explain bitcoin to children of teenagers. In My country I can say 98% children don't know bitcoin. In fact, bitcoin can be future money. If the children not familiar with cryptocurrency or bitcoin, how can they face the digital era in the future.
It seems something a little difficult, because not even adults understand at all cryptocurrency, and its normal, because there has been centuries since we have this appreciation of money, and that suddenly there's another conception, it is of course difficult. But it isn't impossible at all! There are a lot of videos and brochures about the subjects, and you can see a few on propthereum.io