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Science (2015) Grade(s): 1


Construct explanations from observations that objects can be seen only when light is available to illuminate them (e.g., moon being illuminated by the sun, colors and patterns in a kaleidoscope being illuminated when held toward a light).

Unpacked Content

Scientific and Engineering Practices

Constructing Explanations and Designing Solutions

Crosscutting Concepts

Cause and Effect


Students know:
  • Light comes from different sources (natural/man-made).
  • Objects can be seen only when there is a light source.
  • Objects can be seen if they give off their own light.


Students are able to:
  • Gather evidence from observations to support the explanation that objects can only be seen when illuminated.


Students understand that:
  • Objects can be seen only when a light source causes it to be illuminated.


  • light
  • illuminate
  • construct
  • explanation
  • observation
  • available
  • objects