Check this out! Lego makes science kits for teachers that cover DNA and Chromosomes and astronomy and robotics and simple machines, etc. The Teacher kits come with lesson plans and a "demonstration pack" of the specially made Legos for each topic--perfect for homeschoolers with one or two students at a time, plus they're reusable for homeschool groups teaching resource libraries or families who will need to teach the unit more than once. The lessons are written on the middle school/high school level.
I'm just so excited that they offer manipulatives for these very spatial concepts. It may even make sense to DH who was completely mystified by my famous "Thumbs" demonstration of dominant and recessive genes. You see, the thumbs are the dominant genes and the pinkies are recessive genes and the thumbs can obviously beat the pinkies in thumb wrestling so their trait is the one that is expressed. It's only when the pinkies work together that they can have their way... (Anyway, the boys thought it was hilarious.)