Lesson 4

Investigating how light sources create shadows

Lesson Overview

Investigating how light sources create shadows

Throughout this lesson series students will be introduced to how light can create shadows. Students will compare shadows from point and extended light sources such as torches and fluorescent tubes. Students will conduct experiments to see how light sources cause shadows and how the length of shadows can be changed. Students will draw diagrams of shadows by drawing rays to show that light travels in straight lines.

ACS Codes


Lesson Objectives

Students will:

  • Explain how light sources and an object form shadows.
  • Draw diagrams to explain how shadows are created.
  • Investigate the importance of fair testing and how to choose variable to change and remain constant.
  • Make predictions and conduct experiments about the length of shadows.
  • Take measurements of the length of shadows using rulers and digital technologies.
  • Draw diagrams of their observations using rays.

Evidence of Learning

Can the student:

  • Explain and draw diagrams of how shadows are created.
  • Accurately measure the length of a shadow at different times of the day.
  • Make reasoned predictions.
  • Follow the procedures of an experiment.

Example Learning Sequence

  • Observe shadows created in the environment.
  • Discuss how shadows are created when an object blocks the path of light.
  • Measure the length of shadows over the period of the day.
  • Predict the length of shadows based on the size of an object.
  • Use a torch held at different angles to create and measure shadows.
  • Draw diagrams of how shadows are created using rays.