I think we should wait for the right time to teach to them about bitcoin because teaching it to them at young age or minds would be complicated for them but somehow they would able to cope up since we are already on a high technology era. Showing them videos about bitcoin is the most effective for me.
It depends on their curiosity because there are younger kids that are even more active with discoveries and wants to learn a lot with what's new in technology. Maybe if they are just showing interest with bitcoin then we should teach them but if they are not they let's don't waste our time talking to them things about bitcoin.
Kids aren't nessicarily always interested in what you have to say but that doesn't mean you shouldn't say it. Bitcoin's are part of the future and they'll need to know how they work. Why not get them in front of that hurdle? That seems the most logical to me. Even if for whatever reason bitcoins aren't used blockchain technology is here to stay.