Learning Objectives: To describe and demonstrate how the properties of wax can be utilized to make crayons of different shapes and colors.
There is no need to go to the Crayola factory to make crayons. You can melt wax in your own oven from existing crayons to make new crayons of different shapes and designs.
I wanted to make robot crayons so I bought a mold that would survive the hot temperature of the oven. This was the same type of mold that can be used for making chocolate candy. You can also use a muffin pan.
Crayons are made from paraffin wax and color pigment and melt between 120 – 147 F (from Crayola.com). By heating them in the oven the wax changes from a solid to a liquid state. When they cool to room temperature they change back to their solid state once again.
I started by removing the paper wrapping from old crayons. Then I cut up the crayons into small pieces (roughly 1/4 inch) with strong scissors. I placed these pieces into the mold. The mold was placed in a pre-heated oven for a few minutes (~5 to 10 depending on the size of the crayon to be made) until the wax turned to liquid. I next allowed them to cool until the wax solidified, and carefully popped the crayons out of the mold. The cooling time varied depending on size of the crayon. Some of the robots were larger than others.
Here’s a cute video showing two girls making crayons the same way:
In a fun way, this activity shows kids that crayons are made of wax that can change forms when exposed to different temperatures.