Density Rainbow
Five liquids that refuse to mix, stacked in a glass.
- Ages
- 5–12 yrs
- Play
- 20–35 min
- Prep
- 8 min
- Mess
- some
- Energy
- calm
- Where
- at the table
You’ll need
Things you probably have at home.
- a tall clear glass
- sugar
- water
- food coloringGet it on Amazon
Optional
- cooking oil
- dish soapGet it on Amazon
- a dropperGet it on Amazon
- measuring spoonsGet it on Amazon
How to play
Before you start: Make four sugar solutions in separate cups: same amount of warm water each, with 1, 2, 3 and 4 tablespoons of sugar. Color each one differently and stir until fully dissolved.
Pour the most sugary one into the tall glass first.
Tilt the glass and pour the next one very slowly down the inside wall — speed is what ruins this.
Keep going, least sugary last.
Hold it up to the light: the colors sit in bands.
Ask why the heavy one is at the bottom, and connect it to which cup had the most sugar.
What it helps with
Keep it safe
- Warm water, not hot, and an adult does the pouring of anything warm.
Make it different next time
- Add oil on top and watch it refuse to join in.
- Drop a raisin or a grape in and see which layer it stops at.
Cleanup: Down the sink with plenty of water. Sticky glass needs a hot wash.
Three more like this
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Balance And Weigh
20–40 min 4–10 yrs Low mess- kitchen scales, or a coat hanger and two cups
- small things to weigh
Learn something
Walking Water
5–20 min 4–11 yrs Low mess- six clear cups
- food coloring
- paper towels or coffee filters
- water