This morning I stopped by my friend Mike Morrell’s 9th grade science class. It was water rocket launch day so I knew it would be a fun day. Mike’s students have been working on rocket designs and building their rockets for a while. The water rockets are the first phase of the unit. Full model rockets with engines will be launched later this spring.
To get rough measurements of the heights each water rocket reached Mike had students using a clinometer iPad app. You can grab Clinometer HD for free right now. The app has a large read-out so that one student can point the iPad at the rocket while another reads the display to capture the peak angle. After recording the angle and the distance they are standing away from the launch point students were able to calculate the approximate height that the rockets reached. You can read about the process for measuring the height on this NASA page or on this PDF from Estes, a model rocket manufacturer.