If bitcoin or crypto is taught for elementary level classes in my opinion it is impossible because elementary level children's minds will not be able to accommodate lessons about bitcoin which I think will be ignored because it is difficult for them to understand.
and what I know is that applying crypto or bitcoin lessons only high schools and universities tend to be easy to understand and will be directly involved, and what we see is the growth of bitcoin that millennials like today because it is taught in high schools and universities which are very easy to understand and in demand by them.
Maybe they could teach them in a grade 6 level but the basic principle only. It would be hard for them to absorb such kind of information if it would be such deep hence the subject of cryptocurrency wasn't easy as it seems. It was more suitable to teach it in a higher level of education where they can applied it in actual and it can add to their career choices which they would like to pursue. These might be a good choice and for sure these course will become in demand.