Subscribe

4th grade · Science · Unit 2 of 8

Light

Sources, shadows, reflection and refraction

What your child practices

Natural and artificial light, things that make light and things that reflect it, shadows, transparent, translucent and opaque materials, mirrors, refraction, and how light technology affects people and wildlife.

Alaska content standards learning standard: 4-PS4-2 · light reflecting from objects into the eye lets us see them

How we explain it

Children can open this short lesson before they practice.

  1. Light sources make their own light, like the Sun or a lamp. The Moon only reflects sunlight.
  2. Light travels in straight lines, so it can't go around corners. Blocked light makes a shadow.
  3. Mirrors reflect light. Light bends (refracts) when it passes between air, water or glass.
  4. You see an object when light from it enters your eyes.

Example: Why does a pencil in a glass of water look bent? Light from the pencil passes from water into air. Light bends when it moves between materials. This is refraction. Answer: the light refracts (bends)

Light in Alaska

In the Alaska content standards, this is unit 2 of 8 in 4th grade Science, after Sense & Respond and before Sound.

Gradelings describes a child's practice on this unit as Beginning, Approaching, Meeting or Exceeding (Four practice steps). That reflects practice, not a report-card mark: the teacher decides the mark.

Source: Alaska Department of Education and Early Development

Sample questions

A taste of this unit. In the app, questions change every time and get easier or harder to match your child.

  1. Question 1

    Which surface absorbed the most light energy?

    Temperature after 10 minutes in the Sun (°C)
    0510152025303540black paperwhite paperfoil
    • foil
    • white paper
    • black paper

  2. Question 2

    Which surface reflected the most light?

    Temperature after 10 minutes in the Sun (°C)
    05101520253035black paperwhite paperfoil
    • white paper
    • black paper
    • foil

  3. Question 3

    What does a mirror do to light?

    🪞
    • absorbs all of it
    • makes it colder
    • turns it into sound
    • reflects it

  4. Question 4

    Which of these is a natural source of light?

    ⚡
    • a flashlight
    • lightning
    • a lamp
    • a TV

  5. Question 5

    How does light go through it? Tap an item, then tap its basket.

    Sort into: 🔍 transparent · 🌫️ translucent · 🧱 opaque

    • 🪟frosted glass
    • 🪟clear window glass
    • 🚪a wooden door
    • 🧻clear plastic wrap
    • 🍳a metal pan
    • 📄wax paper

  6. Question 6

    What do glasses and telescopes use to help us see better?

    🔭
    • sound
    • batteries only
    • lenses
    • magnets

More 4th grade