Make a Clinometer

Materials - set square, cotton, sellotape, blue tac, cut up rubbers, 1 meter rulers.
Task-  To make a clinometer, so we can measure the height of various objects around the school.

https://www.youtube.com/watch?v=GMLcU1Qknts
Here's a picture of how to make a clinometer.

After we had made the clinometer we measured
The olive tree = 12.5 to 13.5 meters.
Toilet block    = 3.64m.
Norfolk pine  = 30.5m.
Goal posts      = 5.65m.
We had problems sighting the clinometer, but with a bit of practice we got it. It took 2 people to make sure the string and rubber was hanging vertically. We found where to stand if the Norfolk pine  was cut down so we couldn't get hit by the falling tree.