Fizzy Color Eruption Cups Experiment

6-8 small clear cups

White vinegar

Food coloring — a full rainbow set

Baking soda

Tissue paper (for wrapping baking soda bombs)

A large baking tray

Line up cups on a baking tray and fill each halfway with vinegar.

Add a different food coloring to each cup — red, orange, yellow, green, blue, purple.

Wrap tablespoons of baking soda in tissue paper squares to make little bombs.

Line the bombs up next to the cups.

Starting at one end, drop a bomb into each cup in quick succession.

Watch the eruptions cascade down the line — fizzing, overflowing, mixing colors on the tray.

The mixed colors pooling on the tray create a beautiful secondary-color surprise.

The tissue paper delays the reaction by a few seconds while the vinegar dissolves it — this creates a delayed eruption chain effect.

Use clear cups so you can see the colors fizzing from every angle.

The tray catches the overflow, and the mixed colors on the tray are half the show.

Try different amounts of baking soda and predict: "Which cup will erupt biggest?"

This is perfect for a backyard science party activity. Set up stations and let every kid have their own row.