Homemade Sidewalk Chalk: A Fun and Educational STEM Activity for Kids
Looking for a fun and educational activity to do with your kids? Why not try making your own sidewalk chalk? This STEM (science, technology, engineering, and math) activity is perfect for elementary-aged kids and is a great way to get them excited about learning.
In this project, we'll show you how to make your own sidewalk chalk using simple ingredients that you probably already have around the house. We'll also talk about some of the science and chemistry behind this fun activity.
Materials:
- 1 cup plaster of Paris
- 1/2 cup water
- Food coloring (optional)
- Mold or ice cube tray
- Stirring spoon
- Paper towels
Instructions:
- In a large bowl, mix together the plaster of Paris and water until you have a smooth, creamy consistency. If you want to make colored chalk, add a few drops of food coloring at this point.
- Pour the mixture into the mold or ice cube tray. Tap the mold gently on the counter to remove any air bubbles.
- Let the chalk dry for at least 24 hours. (You can also speed up the drying process by placing the mold in the refrigerator or freezer.)
- Once the chalk is dry, pop it out of the mold and enjoy!
The Science Behind Sidewalk Chalk
When you mix plaster of Paris with water, a chemical reaction takes place that forms calcium sulfate dihydrate. This compound is what gives sidewalk chalk its hard, chalky texture.
When you draw on the sidewalk with chalk, the calcium sulfate dihydrate particles are deposited on the surface of the concrete. These particles are held in place by the water molecules that are also present in the chalk. When the water evaporates, the calcium sulfate dihydrate particles are left behind, creating a visible mark.
Educational Benefits of Sidewalk Chalk
In addition to being a fun activity, making sidewalk chalk can also be a great way to teach kids about science and chemistry. Here are a few of the educational benefits of this activity:
- It teaches kids about the properties of matter. By mixing plaster of Paris and water, kids can learn about the different states of matter (solid, liquid, and gas) and how they can change.
- It teaches kids about chemical reactions. The reaction between plaster of Paris and water is a chemical reaction that produces a new substance (calcium sulfate dihydrate). Kids can learn about the different types of chemical reactions and how they can be used to create new materials.
- It encourages kids to be creative. Sidewalk chalk art is a great way for kids to express their creativity and imagination. They can draw pictures, write messages, or even create games.
So what are you waiting for? Get started on your own sidewalk chalk project today!