My favourite kids' show is Tiny Planets, featuring two animated creatures named Bing and Bong, "heroes of the universe." At the beginning of each episode they are given a mission, to salvage some desperate situation on a faraway planet, that centers around a key point of physics (usually). Some examples:
Episode 2 "Snow Problem"
Educational Concept: Rain and snow are different forms of water.
Episode 44 "Flocker Flicker"
Educational Concept: Animation works by presenting a series of still pictures very quickly, one after the other. The result is that the pictures appear to move.
Episode 47 "Flower Power"
Educational Concept: Sound can be directed (Megaphone) so that the listener hears it more loudly.
It's amazing! Helena's a little young to fully grasp these concepts, I know; but I try to watch this show regularly with her, hoping to instill a sense of and wonder at how things work.
(Bong not required for full entertainment value.)