Science Support Materials
Science snapshot: Why does the shadow move around the sundial?
Science/Science Understanding/Earth and space sciences
|Content Description||Relevant aspects of the Achievement Standards|
Earth’s rotation on its axis causes regular changes, including night and day (ACSSU048)
Students use their understanding of the movement of the Earth, materials and the behaviour of heat to suggest explanations for everyday observations.
Nature of the assessment
Purpose of the assessment
To check students’ understanding of the relationship between the rotation of Earth and shadows
Stage in the teaching sequence
Within a lesson sequence. Prior to the lesson the students had made their own sundials and observed the position of the shadow at different times of the day.
- The teacher mocked-up a student work sample showing a question and an incorrect answer.
- The students worked in pairs and had to explain why the student’s answer was incorrect.
The teacher listened to the students’ discussion as they worked and noted conceptions and misconceptions. She observed that a large number of students could not explain why the shadow moved around the clock drawn onto the face of the sundial.
The task also allowed the teacher to observe students in relation to aspects of the General Capabilities. In particular, she focused on one aspect of Creative and Critical Thinking and looked for evidence that students could imagine and consider alternatives.
Using the information
The teacher planned to further investigate students’ understanding of the concept by asking them to draw and share diagrams or use models to explain their reasoning. She planned further tasks to see if students understood the differences between rotating around a central point and revolving on an axis. These tasks included students considering other situations where items revolved such as a Ferris wheel, a spinning top, and a yoyo; and considering the directions of their own shadows and how they changed at different points in the day.