Rain, Mud and Science: 6 Experiments That Need Bad Weather

Outdoor play in bad weather is not a backup plan. Six of the experiments below only work when the weather is bad. On a dry, sunny day in July you could not do a single one of them. You need rain that lands, mud that runs, and a ditch that has suddenly become a river.

What happens outside when it rains?

Rain is water falling from clouds as drops, and every drop is a small experiment. When rain hits the ground it dissolves, carries, collects and disappears again. All six belong to the idea we gathered in autumn as a laboratory. Here they are, in the order the rain leads you through them:

1. Catch drops in flour — each drop becomes a small pellet you can hold.
2. Test the leaves — water beads up on some leaves and spreads out on others.
3. Find the spider web — the invisible becomes visible when drops hang on the threads.
4. Build a dam in the ditch — running water moves sand, and the fastest water moves the most.
5. Count earthworms — they come up onto the path when it is wet.
6. Follow the puddle — mark its edge with sticks and watch it shrink.

Now the surprise. Draw a raindrop and you will probably draw a teardrop with a point on top. But drops caught in flour come out as small round pellets. A falling raindrop is not pointed. Small drops are almost perfectly round, and the largest flatten on the underside, a little like a bread roll.

The rain is not what stops the experiment. The rain is the equipment.

Try it at home: Catch raindrops in flour

You need a baking tray with a rim, enough flour to cover the bottom a couple of centimetres deep, a sieve, a white sheet of paper, a ruler and rain gear. Suitable for ages 4–12.

1. Fill the tray with flour and smooth the surface with the ruler.
2. Hold the tray out in the rain for three or four seconds, then bring it in.
3. Leave it untouched for half an hour so the drops dry into pellets.
4. Pour the flour gently through the sieve over a bowl.
5. Lay the pellets on the white paper from smallest to largest.
6. Measure the biggest and the smallest with the ruler.

⚠️ An adult should choose a spot away from traffic and keep children out of ditches with strong currents.

If the rain gets too heavy, try our rainy day STEAM activities at the kitchen table. When the sun returns, pack an autumn discovery kit and head out again.

What happens if you catch drops on a drizzly day and on a day of pouring rain, and put the pellets side by side?

Questions to wonder about

Where does the water in the puddle go when it disappears?

Why do some leaves get wet and others stay dry in the same rain?

If a raindrop has been a cloud, a river and a puddle before, where has the drop landing on your hand today been?

Every child is made of good atoms. At Good Atoms, we help them discover it.

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