Science · Kindergarten · Sound and Vibration: Grade 1 Preview (NGSS PS4) · Supplemental / Grade 1 Preview

Light and Shadows: Grade 1 Preview (NGSS PS4)

Preview content aligned to NGSS PS4 (Waves and Their Applications in Technologies for Information Transfer). Light and shadows are Grade 1 performance expectations (1-PS4-2, 1-PS4-3), not Kindergarten. Included here as optional enrichment only , not a K NGSS requirement.

About This Topic

Light and shadows offer kindergartners a visible, manipulable entry point into the physics of waves and their interactions with objects. This Grade 1 preview topic, aligned to performance expectations 1-PS4-2 and 1-PS4-3, explores a core behavior of light: it travels in straight lines, it can be blocked by opaque objects, and that blocking produces a shadow. These observations build a concrete foundation for later study of reflection, refraction, and light as an information carrier.

Students discover that a shadow's size and shape change when the light source or the object moves, giving them direct evidence of how light behaves. A flashlight, a hand, and a wall are sufficient for rich exploration. When students move an object toward and away from a flashlight and watch the shadow grow and shrink, they are building an empirical mental model of light-blocking using completely accessible materials and their own bodies.

Active learning is the right approach here because light behavior is best understood by manipulating variables directly. Students who move an object closer to a flashlight and observe the shadow grow develop a causal mental model they can describe in their own words. That hands-on discovery is both more engaging and more accurate than a static diagram, and it produces transferable understanding that students can apply the next time they notice a shadow in daily life.

Key Questions

1. What do we need in order to see the objects around us?
2. How does a shadow change when you move closer to or farther away from a light source?
3. Can you use your hands and a flashlight to make different shadow shapes on the wall?

Learning Objectives

• Identify objects that block light to create shadows.
• Demonstrate how moving an object closer to a light source changes the shadow's size.
• Compare the size of a shadow when an object is close to a light source versus far away.
• Create different shadow shapes using hands and a flashlight.
• Explain that light travels in straight lines to create shadows.

Before You Start

Basic Observation Skills

Why: Students need to be able to observe and describe what they see happening when light is blocked.

Identifying Objects

Why: Students must be able to identify common objects that will be used in the activity, such as flashlights and their own hands.

Key Vocabulary

light source	Something that gives off light, like the sun or a flashlight.
shadow	A dark shape made when an object blocks light.
opaque	An object that light cannot pass through.
block	To stop light from passing through an object.

Watch Out for These Misconceptions

Common Misconception

The shadow is always the same size as the object that made it.

What to Teach Instead

Students commonly expect shadows to match the object's size. The shadow-detectives investigation reveals this directly: moving an object close to the flashlight makes its shadow much larger than the object itself. Physical testing produces this discovery more convincingly than a verbal correction because students observe it themselves and can verify it by moving the object.

Common Misconception

You need sunlight to make a shadow; a flashlight is not strong enough.

What to Teach Instead

Any light source that can be blocked produces a shadow. Darkening a corner and using a flashlight produces clear, traceable shadows that generalize the concept: it is the blocking of light, not the specific source, that makes a shadow. This also gives students a classroom tool they can use independently for their own light investigations.

Active Learning Ideas

Inquiry Circle: Shadow Detectives

Pairs use a flashlight in a darkened corner to cast the shadow of a small cardboard shape onto white paper taped to the wall. They move the shape to three positions: close to the flashlight, halfway, and far away, tracing the shadow outline at each position. Partners compare the three tracings and describe the pattern they see.

30 min·Pairs

Simulation Game: Shadow Puppets

Students create simple paper hand cutouts and use a flashlight to cast shadows on the wall. They experiment with holding the cutout at different angles and distances to change the shape and size of the shadow, then share one discovery using the sentence frame 'When I moved it closer or farther, the shadow...'

20 min·Small Groups

Think-Pair-Share: Where Does the Shadow Go?

Show a photo of a person with a shadow falling to their left. Ask students: if the sun moved to the other side, where would the shadow be? Partners share predictions, then use a flashlight and a small figure to test them. Pairs report their result and whether it matched their prediction.

15 min·Pairs

Gallery Walk: Our Shadow Tracings

Each pair posts their three shadow tracings labeled near, middle, and far. Students walk the gallery and place a sticky dot on the tracing that shows the biggest shadow. After the walk, the class reads the pattern together and explains in their own words why the near shadow is the biggest.

20 min·Whole Class

Real-World Connections

• Stagehands and lighting designers use flashlights and other light sources to create shadows for theatrical performances, shaping the mood and focus of a scene.
• Photographers use light sources and objects to control shadows and highlights, influencing the texture and depth of their images.
• Children playing with shadow puppets use their hands and a light source to entertain themselves and tell stories.

Assessment Ideas

Exit Ticket

Give students a card with a picture of a flashlight and a ball. Ask them to draw where the shadow would be. Then, ask them to draw what happens to the shadow if the ball moves closer to the flashlight.

Quick Check

During the activity, ask students: 'Hold up your hand between the flashlight and the wall. What do you see?' Then, ask: 'What happens to the shadow if you move your hand closer to the wall? What if you move it closer to the flashlight?'

Discussion Prompt

Gather students and ask: 'What do we need to make a shadow? What happens to the shadow when we move the object closer to the light? What happens when we move it farther away? Can you show me with your hands?'

Frequently Asked Questions

Why are light and shadows included as kindergarten content if they are Grade 1 standards?

These concepts are included here as optional enrichment only, not as kindergarten grade-level requirements. Standards 1-PS4-2 and 1-PS4-3 belong to Grade 1. Early exposure builds vocabulary and physical intuitions that make Grade 1 instruction more productive. Many teachers include this content in late kindergarten as a natural extension of investigation skills and as a bridge to the following year.

What materials do I need for a light and shadows investigation?

A standard classroom flashlight, a darkened corner or closet, white paper taped to the wall, and small opaque objects such as cardboard shapes or toy figures are sufficient. For tracing shadow outlines, tape the paper before starting so students can mark positions with a pencil. No specialized equipment is needed, and setup takes under two minutes.

How do I handle the question of whether clear plastic or glass makes a shadow?

This is an excellent observation to encourage. Transparent objects block very little light, so they produce faint or no shadow, while opaque objects block it fully. Testing a clear plastic cup alongside a cardboard shape gives students an immediate comparison and introduces the idea that different materials interact with light differently, which connects naturally to Grade 1 content on materials and light.

How does shadow exploration connect to active learning approaches?

Shadow tracing and puppet play give students a goal-directed reason to manipulate light variables, which maintains engagement while generating observations they can describe and compare. When students try to make the largest possible shadow or match a specific shape, they are testing hypotheses with immediate visual feedback. That predict-test-observe cycle is the foundation of scientific thinking at this age.