These seem like the sort of thing you might be looking for. There are
instructions for simple machines that teach kids about different mechanical
principals--gears, levers etc.
Hey, I just looked, and it seems like these are still available new:
I am hoping to teach a Lego class for the University of Utah this summer. I am "required to prepare and submit a class syllabus and an outline of topics to be discussed. Legomania I: Ages 7-9. Creates hands-on activities to teach students about (...) (21 years ago, 26-May-04, to lugnet.general, lugnet.space)