Shadow Studies

Third grade scientists began their year-long shadow study this month. Each month, at the same time of day, Third Grade Science Teacher Cecilia Owens brings her students out to the Quad to use the rudimentary sundials they fashioned out of modeling clay and construction paper. They line the sundial up within the sidewalk quadrants and sketch the shadow that falls across their paper. As the year progresses, the shadows will lengthen at first and then get shorter after the Winter Solstice. With their shadow sketches, students can track the sun’s position in the sky over the changing seasons. 

This experiment serves a dual purpose: teaching students about the changing relationship of the sun to the earth and its effect on the seasons and introducing the elements of the scientific method. Students will practice good data collection, tracking the same object, at the same time of day, at the same spot on the patio, and lining themselves up the same way within the geometric grid of the sidewalk. Cecilia explains the concept of variables to her students and the importance of keeping all aspects of the experiment the same to ensure that the elapsed time between months is the only variable. Students follow up each month’s sketch of their sundial’s shadow with a prediction about what they think the shadow will look like the following month. As the days get longer and the shadows shorten, they will discuss how the sun has more time to get higher in the sky as the earth is revolving and rotating and the sun is in a different position relative to the earth. The third grade shadow study is punctuated by the dramatic changes that students observe when daylight savings time ends in November and when it starts again in March. “I try to time it in November, so we go outside the week after the clocks reset,” says Cecilia. “It may have been three weeks since we last observed our shadows, but all of a sudden, there’s this really significant change, and we have the opportunity to talk through why that is.”