Sidewalk Paint!

Brilliant and easy! Equal parts cornstarch and water, and enough food colouring to get the colour you want. It dries to a chalky finish, but we found the colour to be very bright, possibly because I was using Neon colours.

The kids loooved it!
Tip: Get the cheapest paint brushes you can find in the hardware store: the sidewalk is rough and chews them up.

The sidewalk outside my home was a brilliant mess of happy colours … until the next rain, when it washed right away! Perfect!