An outdoor observation that unfolds across a single sunny day. The child traces their own (or a stick’s) shadow with chalk in the morning, again at midday, again in the afternoon — and is genuinely surprised by how much it moves and changes shape.
- Pick a sunny day with at least three sun-out windows (morning, midday, afternoon).
- In the morning (around 9–10 am), stand the child or a vertical stick / wooden spoon on a flat patch of pavement. Trace the shadow with chalk. Trace the child’s feet too (so they stand in the same place later) or mark the stick’s base. Write the time inside the shadow with chalk.
- Predict together: “Where do you think your shadow will be at lunch? Closer? Farther? Bigger? Smaller?” Have the child place a small chalk X where they predict.
- At midday (around 12–1 pm), come back. Stand in the same feet tracings (or replant the stick at the same mark). Trace the new shadow in a different chalk color. Write the new time. Was the X right?
- Predict for the afternoon (around 3–4 pm). Mark another X.
- At the afternoon visit, trace one more time in a third color.
- Stand back and look at the three shadows together. What changed? Most kids notice: shadow is shorter at midday, longer in morning and afternoon, points different directions.
Variation: shadow tag / shadow shapes — try to step on each other’s shadows; make shadow animals with hands. Indoor flashlight version — on a cloudy day, hold a flashlight at three different heights against a wall and trace the cup’s shadow at each. Same-place monthly check — repeat the same midday tracing once a month for a year (winter shadows are dramatically longer than summer).
Requirements
- Space: A flat sunny patch of pavement, driveway, or schoolyard at least 2 m × 2 m
- Surface: Hard, chalk-friendly (concrete, asphalt, paving stones); a yoga mat or paper roll works on grass
- Materials: Sidewalk chalk in 3+ colors, a vertical object (a stick, wooden spoon, or the child themselves), optional sun hat and sunscreen, optional weight to anchor a stick
- Participants: 1 adult + 1 child; sibling/group versions work fine
- Supervision: Moderate — adult plans visit times, watches for sun safety, and chooses a safe pavement spot
Rationale & Objective
NGSS K-PS3-1 (“make observations to determine the effect of sunlight on Earth’s surface”) is a direct match. Shadow exploration is the paradigmatic preschool astronomy / Earth-science investigation (Worth & Grollman dedicate a full chapter to it; Mystery Science and Ashbrook NSTA cover it repeatedly). Critically, the goal at age 5 is pattern recognition, not mechanism — research (Vosniadou) shows few children before age 7 grasp the heliocentric explanation. What 5-year- olds can learn is the daily pattern (shadows shrink toward midday, stretch in morning and evening, change direction across the day). The activity hits HighScope’s Observing, Predicting, and Drawing conclusions KDIs and gives the child a felt experience of measurement and comparison.
Progress Indicators
- Early: doesn’t notice the shadow has moved between visits; predicts the X in the same place as the previous trace; loses interest after the first trace
- Developing: notices the shadow moved but not how; predicts the X with adult prompting; uses comparison words (“longer” or “shorter”) with help
- Proficient: predicts that the shadow will move and gives a reason (“because the sun is over there now”); spontaneously notices the midday shadow is the shortest; describes direction with words like “left,” “right,” “toward the house”
- Advanced: predicts the direction the shadow will move and is right; remembers from a previous day that midday shadows are shortest; relates shadow position to sun position (“the sun is over my left, so the shadow goes right”); proposes a new test (“what if we do this in winter?”)
Safety Notes
- Sun / UV exposure is the main risk — three outdoor visits across midday can mean 30–90 minutes total in peak UV. EPA SunWise: sunscreen SPF 30+, wide-brim hat, sunglasses, water bottle. Avoid 10am–4pm peak in summer when possible; or do all three checks within a 2-hour window in shoulder seasons
- Heat / dehydration — keep water nearby; shorten on hot days; consider an indoor flashlight version on the hottest days
- Never let the child look directly at the sun. Frame conversation around the shadow on the ground, not the source. Sunglasses help
- Pavement traffic — pick a driveway, garage forecourt, or schoolyard, not a sidewalk by the road
- Chalk dust on hands; avoid eye-rubbing; wash hands after
- Watch for stinging insects on warm pavement (bees on clover, wasps on dropped fruit)
- Bare feet on hot asphalt is a burn risk — keep shoes on
Hints
- Playfulness: call it the “Shadow Spy” mission. Use bright sidewalk chalk in fun colors (one color per visit, so the child can read the day across colors). Take a photo from above at each visit; the time-lapse is striking
- Sustain interest: seasonal repeats — same patch in summer and winter shows shadows of very different length. Add a “shadow art” round where the child poses dramatically (arms out, leg up) and the adult traces
- Common mistake: trying to teach Earth’s rotation to the 5-year-old. Developmentally premature; stick to the observable pattern. Also: forgetting to mark the stick base or the child’s feet — the traces become uncomparable. And same-color chalk for every trace makes the day’s pattern unreadable
- Limited space / no sun: indoor flashlight version on a wall — same physics, controllable, no UV. A cardboard tube cut from a kitchen roll standing on a paper plate makes a tabletop sundial
- Cross-domain: measure each shadow with a piece of string (numeracy and tools); compare shadow lengths across visits (ordering); name compass directions if known (geography); draw the sun in the corner of the page where it must have been (spatial reasoning)
- Progression: trace at 2 times → trace at 3 times → predict before each new trace → measure shadow length with string → repeat across seasons → make a hand-drawn “shadow clock” by tracing the stick’s shadow every hour
Sources
- Worth, K. & Grollman, S. (2003). *Worms, Shadows, and Whirlpools*. Heinemann / NAEYC (full chapter on shadows)
- Ashbrook, P. (NSTA *Science and Children* — "Early Years" pieces on shadow play); Ashbrook *Science Learning in the Early Years* (NSTA Press, 2016)
- Mystery Science (Doug Peltz) — "Could a statue's shadow move?" (K, aligned with K-PS3-1)
- California Academy of Sciences — "Which Way is North?" sun-stick teacher resource
- NGSS K-PS3-1 and K-PS3-2 (effect of sunlight on Earth's surface), 1-ESS1-1 (patterns in the sky)
- HighScope KDIs — Observing, Predicting, Drawing conclusions, Natural and physical world
- Head Start ELOF — Scientific Reasoning (P-SCI 1, 5)
- Teaching Strategies GOLD Objective 24 (scientific inquiry), Objective 27 (Earth's environment)
- Vosniadou, S. — research on children's mental models of the Earth and sky (relevance: keep at pattern level, not mechanism, at age 5)
- EPA SunWise; AAP HealthyChildren — Sun Safety guidance for children