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Indoor activity

Colour Mixing Lab

Set up a kitchen colour science lab and discover how red, yellow, and blue combine to make every shade of the rainbow — plus the magic of oil and water!

Ages 3-6 1 hour Education 8/10

Materials

  • Food Colouring
  • Paper
  • Small Containers
  • Vegetable Oil

Illustrated Steps

1

Set Up the Lab Stations

Fill three containers with water, adding red, blue, and yellow food colouring to one each. Leave three containers empty for mixing.

2

Mix the Primary Colours

Pour red into yellow, blue into yellow, red into blue. Name each new colour and press wet fingertips onto paper to record colour swatches.

3

Discover the Rainbow Layers

Pour vegetable oil into a tall container, then add coloured water on top. Watch the layers form and swirl them gently.

What You’ll Create

A dazzling colour science lab on your kitchen table! 🌈 Using just food colouring, small containers, and vegetable oil, your little scientist will discover how primary colours combine to make new ones — and why oil and water stubbornly refuse to mix no matter how hard you try.

How to Set It Up

Step 1: Set Up the Lab Stations

Line up six small containers on a tray. Fill three with a little water and add a few drops of food colouring — one red, one blue, one yellow. Leave the other three containers empty, ready for mixing experiments. This is the laboratory!

Step 2: Mix the Primary Colours

Pour a little red water into a yellow water container — what colour appears? Try all three combinations (red + yellow, blue + yellow, red + blue) and name the new colours together. Record discoveries on paper by pressing a wet fingertip to make colour swatches.

Step 3: Discover the Rainbow Layers

Pour a centimetre of vegetable oil into a tall clear container. Gently pour coloured water on top and watch the layers form — oil floats! Swirl gently and watch the colours swirl through each other without truly mixing.

Have fun!

  • 🔬 Mix all three primary colours together — what mysterious colour appears?
  • 💧 Add drops of a second colour into the oil layer and watch them sink through
  • 🌈 Can you make all six rainbow colours in a row of containers?
  • 🎨 Dip a strip of paper into each colour and make a rainbow bookmark

Why It’s Amazing

  • Early Science: Colour mixing is a child’s very first chemistry experiment — safe, simple, and magical! 🧪
  • Colour Theory: Understanding primary and secondary colours underpins all art and design thinking. 🎨
  • Observation Skills: Watching oil and water separate builds keen scientific curiosity and careful looking. 🔍
  • Sensory Play: The visual impact of swirling colours is deeply calming and engaging for young children. 🌟

Pro Tips

For ages 3–4: Use just two colours at first. The moment red + blue = purple appears is pure magic — that’s enough for one session!

For ages 4–5: Introduce the names “primary” and “secondary” colours — children this age adore impressive vocabulary.

Protect the table with a plastic sheet or do this activity in the kitchen sink for completely stress-free clean-up!