I wasn't too excited about doing the muscular system since I wasn't sure what we were going to do for it but L really wanted to do it next so here is what we came up with.
We read some books from the library and talked about the three different types of muscles-smooth, cardiac and skeletal. We also talked about how muscles work in pairs and L did an experiment observing how her bicep and tricep work together.
Together we made this model of how the muscles work on the arm using elastics. The cardboard tubes represent the bones of the arm. It was pretty tricky getting the elastics to fit into the holes and tie them etc. As L lowered her arm she could see how the elastic expanded and contracted.
L added the muscles to her body using tissue paper. She drew red lines with a crayon to represent the stripes in the muscles. She then labeled the major muscles.
During the labelling Daddy came home and it was perfect timing as when he got out of the shower I asked him to come to the kitchen with his shirt off. He has very little body fat so we were able to see each of the major muscles in action and L was able to name them.
Next up was seeing how the tendons work on the hand. I found a tutorial here. L and I cut the straws and she threaded embroidery thread into them and L tied a bead to the end. I did the tricky work of taping the straws to the paper.
It was really neat to see how pulling the threads all together would make the fingers move or just pulling one would make that finger move.