Fizzy Sidewalk Chalk Paint Activity

Baking soda and cornstarch (equal parts)

Water

Food coloring in multiple colors

Cups for mixing

A spray bottle filled with white vinegar

Paintbrushes (optional)

Mix equal parts baking soda and cornstarch. Add water until you get paint consistency.

Divide into cups and add different colors to each.

Head outside to a sidewalk or driveway.

Paint designs directly onto the pavement — pour, brush, or squeeze from bottles.

Create pictures, names, or abstract art.

Fill a spray bottle with vinegar.

Spray over the painted surface and watch it fizz, foam, and react. The whole sidewalk bubbles.

The fizzing reaction is the same baking soda + vinegar chemistry, but at a massive outdoor scale.

Everything washes away with rain or a hose. Zero permanent mess.

The combination of tactile painting, visual color, and the fizzing reaction hits multiple senses simultaneously.

Challenge your child to paint a scene first, then the vinegar 'reveal' adds the final fizzy effect.

This is a fantastic activity for neighborhood play — set up stations for multiple kids.