Very nice well done and good thinking. I do not have children but I would so the same. I do this for my future and keep a small amount so far some I'm new but an extra $50 here and there can add up.
You do not need to save thousands of dollars every week in order to have a good future, the most important thing when saving is to start as soon as possible if you are able to do that then you are surely going to have a better future than a person that does not and if you save in bitcoin your future is going to be even better thanks to the fact that bitcoin is always going up in value in the long term.