Like cash it doesnt really teach kids even some adults about how to properly manage spending. It really depends on the person using bitcoin, it also depends on the people around that person or kinds who will teach and remind them about handling and managing their bitcoin. If we will teach kids about proper way of spending and saving its better to show them how to do it not just by words but also by example.
We do not need money to teach about kids about saving, you could use candy, you could give to them some candy and tell them that if they keep that candy for some days that they are going to receive more candy in return then you explain to them the same happens to money and bitcoin and they are going to be able to grasp the concept immediately and understand the concept of saving.
I think the kids can learn from their elders how they are saving and investing and the best place for their learning is bitcoin world. I mean if I invest in bitcoin and tell my son that I have bought some digital currency which is not only a digital coin business but also like a regular currency. I can use my bitcoin anywhere in the world for purchasing anything. My kid will definitely take keen interest in bitcoin and for which he will try to save.