I spotted this excellent human body model in a classroom at the primary school last year. He spends most of his time in storage. I asked if we could borrow him to have at home for a week, and the school were happy enough. The boys are very interested in it. Michael has been reproducing human body cross section diagrams for a while now, so I knew he would be interested in getting his hands on some rubber lungs.
Worrying cautionary note: we had dinner with in-laws last night including the boys' cousins' cousins, who are 10 and 14. The boys were very impressed with Lara particularly. When we got home Michael wanted to do a drawing of Lara before bed. After five minutes I yelled out from downstairs "come on - have you finished the drawing of Lara? Its time for bed!!" Marcus called "Yes, he's finished, now he's drawing the intestines".