Weather School / First Weather · ages 2 to 5
Rainbows
What does it take to build a rainbow?
The mission: guess first, then go look
Guess what the sky needs to make a rainbow: sun, rain, or both at the very same time.
When the rain is ending and the sun comes back, stand with the sun behind you and look at the rainy side of the sky. Both. It always takes both.
A rainbow needs two things in the sky at the same time: sunshine and rain.
Sunlight looks white, but it is really every colour riding together.
When sunlight shines through raindrops, the drops spread the colours out into a bow.
Professor Weather Rock says
Every rainbow is really a full circle, like a ring. The ground hides the bottom half, which is why you only ever see the bow.
Rocktivity Time!
Pick a door. Every door is a good one.
Move like the weather
Paint a rainbow bigger than you. Start crouched down on one side and swoop your arm up and over to the other side, one giant bow. Again, even higher. Say the colours while you paint.
Ask them
“How many colours can you see in it?”
The Rocktivity
Hunt for tiny rainbows indoors: a glass of water on a sunny windowsill, the shiny edge of a mirror, a soap bubble. Rainbows hide in small places on dry days.
On a sunny day, try this
Make your own rain: have a grown-up spray a fine mist from the hose with the sun behind you. Guess where the rainbow will appear before the water flies. Sunshine plus water drops is the entire recipe, and now you own it.
Is the rock right?
You looked with your own eyes. The rock is outside looking too. Ask it what it sees, then decide together who read the sky better.
Words we learned
For the grown-up
The hose rainbow is the real thing, built from sunlight and water drops exactly like the big one. Sun behind you, drops in front: that geometry is the whole recipe, and it is also why nobody has ever walked to the end of one.
Rocktivity
Take it off the screen
A colouring sheet with the big word to trace, plus the whole lesson in print. Free for any home or classroom.
The trail continues
A rainbow is sunlight showing off. On the next bright morning, go catch the sun doing its everyday trick instead: step outside and find where your shadow is hiding.
Sunny Days knows why it follows you everywhere.