CD Spectroscope

  • Math Brainteaser: [5-10 minutes] – (Blank)
  • Hook: [5 minutes] – Ask students if they’ve ever seen a rainbow and why they think it appears.
  • Lesson and Activity: [20 minutes] – Build the spectroscope and explore light sources.
  • Cleanup and Discussion: [10 minutes] – Questions: “What did you notice about the light spectrum from different sources?” “How does this experiment help us understand light?”


  • An Old CD or DVD: To diffract the light.
  • Black Construction Paper: To make the body of the spectroscope.
  • A Box or Tube (like a paper towel tube): As the structure of the spectroscope.
  • Scissors or Box Cutter: To cut the paper and box.
  • Tape or Glue: To assemble the spectroscope.
  • Ruler and Marker: For measuring and marking.
  • A Small Slit: Can be made using a razor blade or cut precisely in the tube.