CurriculumGrade 4Science

How We See Things

Aligned to 4-PS4-2 — Next Generation Science Standards.

What this lesson teaches

We see objects when light bounces off them and travels into our eyes. In a completely dark room with no light at all, our eyes cannot see anything.

Worked example

You can see a red apple because light hits it, bounces off, and enters your eyes. Turn off every light and the apple seems to vanish — even though it is still sitting there.

Practice questions

  1. Look around a bright room, then picture it with the lights off. Why can't you see in total darkness?
  2. Draw arrows showing light traveling from a lamp, to a book, and then into an eye.
  3. Explain why you cannot see any object in a room that has no light at all.

Watch the lesson

Every lesson comes with a video taught in English and Spanish — the same video the QR code in the printed workbook opens.

▶ Watch this lesson

En español

Cómo vemos las cosas

Vemos los objetos cuando la luz rebota en ellos y viaja hasta nuestros ojos. En un cuarto completamente oscuro, sin nada de luz, nuestros ojos no pueden ver nada.

Ejemplo: Puedes ver una manzana roja porque la luz la golpea, rebota y entra a tus ojos. Apaga todas las luces y la manzana parece desaparecer — aunque sigue ahí.

More Physical Science lessons

Energy and Energy Transfer4-PS3Waves: Amplitude & Wavelength4-PS4How Energy Travels4-PS3-2When Things Collide4-PS3-3Energy-Changing Machines4-PS3-4Sending Messages with Patterns4-PS4-3

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