In any case, do you really think kids even want something that is relevant to their daily lives? You think something practical like compound interest is going to get them excited? People enjoy fantasy, and that is just what mathematics can provide - a relief from daily life, an anodyne to the practical workaday world.
Illusion is an anodyne, bred by the gap between wish and reality.
Time passes, Time the consoler, Time the anodyne.
There is no self-delusion more fatal than that which makes the conscience dreamy with the anodyne of lofty sentiments, while the life is groveling and sensual