Scholarship CPD Day – National STEM Learning Centre

Sundials – Peter Ransom


What do pupils take home from mathematics lessons? Homework? Worksheets? Textbooks? Nothing?  This is the question that stuck with me the most following Peters presentation, it made me question how exciting and applicable my own lessons are from the perspective of my pupils. 

Peters session explored the life of John Blagrave, a 15th Century Mathematician who published 4 books over the course of his life, with a focus on his work with sundials. After covering some terminology and theory, the first task was to construct our own sundial using a coat hanger, small plastic bottle, paper and a pen. Firstly, we measured the circumference of the bottle and drew our time scale out on paper, the next step was to insert the coast hanger through the bottle (there were two holes, one in the top and one in the bottom). Next, we had to bend the wire at the base to an angle of 54°, the latitude of York, to ensure the sundial was accurate, and finally, glue on the time scale to the back of the bottle. And there you have it, your very own sundial!

Following the construction of the sundial, Peter talked us through the mathematics behind the sundial and how it can be applied in the classroom setting. How the earth’s axis of rotation and the equator have a fundamental part to play when constructing sundials. One of the simplest, most accessible tasks was merely figuring out the angle through which the sun moved in relation to earth in an hour, a minute and a second. The tasks that followed were applications of sundials in the real world, how to adjust the sundials output when the shadow cast on the sundial was ahead / behind of clock time due to the earths rotation around the sun. This was accomplished using graphs provided showing how the local solar time was affected at different times of the year.

From my perspective, the whole premise of this activity was appealing as it allowed the pupils to see how important the mathematics that they are currently learning was in the past and still is today. It provides the opportunity to discuss interesting parts of our history and other interesting facts, for example, did you know that the U.K has the highest density of sundials per square kilometre in the world?!


By Luke Savin