well kids like to play, so something that can bring together bitcoin and gaming
like puzzle that when solved reveal a private key for example
it is important that kids start to learn early some basic economy, at least something about income and expenditure
i heard about a new law for some countries that will make it possible(to teach them basic economy) in schools
I think. It's hard to teach kids something that they haven't done before like bitcoin, so the first thing to do is to teach children a little knowledge about economics, second is to teach them step by step about bitcoin, what bitcoin is and what are the advantages of it. The best way of learning is to involve them than telling or discussing what bitcoin is all about, and teach them what is important to earning bitcoin for their future.