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.
If you want to explain bitcoin on a teenager or a child mke sure they are enough to understand all the thins that might come out to your mouth. I suggest that first you know a way on how to get a money without getting involve on any job. Then explain to them what is bitcoin, who makes bitcoin and etc. Afterwards, tell them what are the benefits that they can gain from bitcoin. Tell them how important bitcoin is while they were young.