Follows on from "Navigation By the North Star - Introduction" to discuss making a sextant to find latitude using the North Star.
(3) How to Make a Crude Sextant and How a Sextant Works
It is possible to make a crude sextant (capable of detecting to the nearest degree) using classroom materials such as a protractor, fishing line, and a weight.
(4) How to Determine Latitude Using a Sextant and the North Star
The sextant that students made in part three can be used to determine the angle of elevation relative to the horizon of the North Star. This angle is in fact equal to the latitude that they are on.