I gave this project to both geometry and PreCalculus students. I gave them specific directions (included) on how to make a clinometer, but taught them nothing else about how to use them. They had to figure out how to use trigonometry to find the height of some objects in our commons (on a nice day, it would be awesome to go outside). Students used a lot of trial and error, and found how important it was to have an accurate diagram. I checked in frequently with each group-common errors included n