I read about something like this in an Australian elementary school being attended by kids from lower income class. It educates them about how crypto currencies can help them improve their lives by relying on technological advances. I think they have also created their own coin in the process to better understand how these things work.
I don't think to involve children in learning cryptocurrency is a good idea. I think that the knowledge that you need to know can be taught in high school as an elective. Bitcoin is not only currency. This new view of the world. It's the atmosphere of total freedom. The person should be mentally ready for it. The fact that bitcoin is a lot of random people brings only harm to the cryptocurrency.