Raindrops, Rulers and Rainbow Maths
Rainy days don’t have to mean cabin fever, they can be perfect for exploring patterns, measurement, and a little colour magic. Grab a coat, a brolly, a ruler, and maybe a flask of something warm. There’s a lot to learn in those puddles.

There’s something about rain that slows the world down. It presses pause on the rush, inviting us to look closer at how water gathers, drips, joins, and runs away again. Children notice this before we do. Do you remember the days when you sat at the window choosing a raindrop and seeing if it wins the race?
Sometimes we’re tempted to hurry them inside, to dry off and “get back to work.” But what if this was the work? Watching, measuring, comparing: it’s all the language of maths. And The Rhythm of the Rain on a hood? That’s the rhythm of curiosity.
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Measuring Puddles
Take a ruler or measuring tape on your walk. Guess which puddle is deepest, then test your predictions. Compare: “This one’s twice as deep as that one.” Use vocabulary like deeper, wider, longer. You’ve just introduced comparative language and estimation.
Raindrop Races
On a windowpane, pick two raindrops. Each person chooses one and watches whose drop reaches the bottom first. Talk about speed, distance, gravity, and surface tension (in simple terms: “Why do some drops join and go faster?”). Get the timers out or simply count how long it takes in seconds. “How many seconds between the winner and second place”).

Rainfall Jar
Place a clear jar or tub outside on a rainy day, that’s your homemade rain gauge. After the rain stops, measure how much water has collected using a ruler. Record the results in a notebook or make a weekly chart. Compare rainfall between days or even between different spots in your garden. It’s hands-on data collection, and children love seeing the numbers grow and change.
Rainbow Maths
If the sun peeks through, look for a rainbow. Count its colours, talk about light refraction, or make your own with a glass of water and sunlight. Indoors, you can use coloured paper or building blocks to make repeating colour patterns, this is early algebra, disguised as play.
Water Volume Play
Grab a few cups and containers. Estimate and pour. “How many small cups fill this jug?” That’s early multiplication learning in motion.

Symmetry in Reflection
Look at puddle reflections: trees, clouds, even your boots. Point out how the images mirror each other. Children can draw what they see to explore the concept of symmetry.
Simple Conversation Starters
- “Why do puddles form in the same places?”
- “What happens if we jump in the middle versus the edge?”
- “How do you think the water knows where to go?”
- “Can you spot your reflection in the puddle?”
A Little Perspective
Maths in the rain is real maths, it’s alive, sensory, and connected. Children aren’t just counting puddles; they’re learning to make sense of patterns, test ideas, and trust their observations. That’s the foundation of numeracy and confidence.
So next time it starts pouring down, race to the window or step outside. Let curiosity do the counting.
Join the Adventure
If you love the idea of learning that feels like living, you’ll feel right at home in The Joyful Discovery Club.
Each month we follow a new theme in the Adventurer and Discovery Tier. It’s packed with hands-on ideas, conversation starters, and child-led activities that bring curiosity back to centre stage. Not only that, there are activities to cover all learning styles and rainy day activities for family enjoyment.
No pressure. No perfection.
Just families learning side by side, one rainy day and two drenched kid at a time.

