My Grade 8's have been learning about the respiratory system in science. This week, we made models of the respiratory system using a pop bottle, a balloon, and a plastic shopping bag. I got the idea from Habits from the Heart and created a lab worksheet for my Grade 8's to follow. I have guided the students through all the labs we've done up until this point, but for this lab, I stepped back and let the kids take the lead. I told them that I would help if they got stuck, but it was their job to work with their partner to follow the instructions on the handout. Most of the kids followed the instructions very well, but the trickiest part was creating the handle on the bag, and securing the elastic band. Here is one of the finished models: I loved going around to the different tables to see the reactions from the students when they pulled and pushed the diaphragms (plastic bags) of their models and saw the lungs (balloons) inflate and deflate. They wer