Things You'll Need
6 egg shells
Paper towels or soap molds
How to Make Eggshell Chalk. It's easy and fun to make eggshell chalk for your children to draw and color with outside on the sidewalks or driveways. Eggshell chalk should only be used outside and never be used on chalkboards. Here's how to make eggshell chalk with your children.
Break 6 eggs in a bowl. Discard the eggs, clean out the shells and then wash and thoroughly dry the empty eggshells to make eggshell chalk.
Break up the eggshells and place in a bowl.
Grind the eggshells into small pieces with the back of a spoon until the shells become a fine powder. A mortar and pestle works great for this process.
Mix together 1 tsp. of flour and 1 tsp. of very hot water. Add 1 Tbsp. of the ground egg shell powder and mix it together until it is a thick paste. This amount will make one piece of chalk.
Add one or two drops of food coloring to the paste if you want your chalk to be colored. If you want white chalk, just don't add any food coloring.
Shape the paste into chalk sticks and roll them up in a paper towel, wrapping them tightly.
Allow the sticks of chalk to dry for 3 days. Your eggshell chalk will then be ready to use.
Put the eggshell paste mixture into soap molds to make chalk in different shapes. Let it dry for 3 days before use. Grind the eggshells outside on the sidewalk, or any other concrete surface, by using a rock for grinding. Make sure the rock and the concrete surface are both clean so that no dirt gets into the ground shells. Plan how to use the eggs so they're not wasted.