Summer Science Experiments for Kids- Sidewalk Chalk

Summer is soon slipping away, but we’ve got time for one more fun summer science experiment.  It’s time for Sidewalk (or driveway) Chalk!

With only a couple of low-cost items, kids can experiment to make the best recipe for Sidewalk Chalk.

Here’s what you need:

• Plaster of Paris (powder)
• Paper Cups (the waxy ones)
• Craft sticks or plastic spoons (for stirring)
• Water
• Tempera Paint or Food Coloring

Mix the Plaster of Paris with water and one (or more) paint/food colors.  Be sure to document how much plaster and water is being added so you can generate the perfect sidewalk chalk.  Work quickly because the plaster will dry fast in this summer heat.  Pour each “recipe” into a separate cup and let sit.  Once dry, peel away the waxy paper cup to reveal the stick of chalk and try it out!  Which recipe works the best?  How does using the paint/food coloring affect your recipe?  What could you add to improve the recipe?

Happy Experimenting!

For more ideas to implement STEM, try Five Easy Steps to Implement STEM