What you need
- A straight stick, a wooden spoon or a pencil taped upright to a stone
- A sunny patch of terrace, balcony or compound that stays sunny all day
- Chalk, or small stones to mark with
- Paper and pen to record the times
How to play
- 1
Plant the stick in the morning
Around nine o'clock, stand the stick upright in a spot that will get sun all day. Make sure it cannot fall or be moved — the whole experiment depends on it staying put.
- 2
Mark the first shadow
Draw a chalk line along the shadow and write the time at the end of it. Also note how long it is, in hand-spans.
- 3
Come back every hour
Same thing each time: new line, time written at the end, length in hand-spans. Setting a phone alarm keeps it going when interest dips.
- 4
Ask for a prediction at noon
Before the next mark, ask 'where will it be at two o'clock, and will it be longer or shorter?' Let them mark their guess in a different colour.
- 5
Look at the whole fan in the evening
By five o'clock there is a fan of lines. Ask what they notice. Most children spot both patterns themselves: the shadow swings around, and it is shortest in the middle of the day.
- 6
Test it the next day
Cover the clock face with a cloth, then check the time by shadow alone before looking at a phone. A tool you built and then trusted feels different from one you were given.
What your child is learning
Honestly stated — this is what the activity actually builds, not a list of everything it might touch.
- Noticing a pattern by collecting data over hours
- Predicting the next result and checking it
- That the sun's apparent movement is what makes shadows shift
- Measuring with a consistent unit, even a hand-span
Most of what a child learns about the solar system arrives as facts to be remembered. This is one of the few times they can watch a piece of it happen with their own eyes, over a single day, in their own building.
It also takes almost no effort. Five minutes an hour, seven times, and the rest of the day is free.
The question worth asking
At the end, ask: “did the sun move, or did we?” Most children under ten will say the sun moved, because that is exactly what it looks like. Do not rush to correct it. Ask how they could tell the difference. There is no need to reach the right answer today — sitting with a hard question is the useful part.
If the day is cloudy
Use a torch instead. Fix the stick on a table in a dark room and walk the torch slowly in an arc above it. The shadow does the same sweep, and the connection between the light’s position and the shadow’s direction becomes obvious in thirty seconds.
Ways to take it further
- Repeat it a month later, same stick, same spot. The noon shadow will be a different length. That difference is the seasons, measured at home.
- Mark only the noon shadow, once a week for a term. A slow, patient record is a real scientific habit.
- Measure your own shadow at nine, at noon and at five. Same person, three very different heights on the floor.
Do not let them look directly at the sun, and keep the marking short if the terrace is hot. Early morning and late afternoon rounds are the pleasant ones.
Published 8 August 2026 · Suitable for Early schooler, Big kid