autumn days

Saturday, June 9, 2012

homemade chalk

A teacher friend gave us some old powdered tempera paints and told us we could make chalk.  Months later we have finally found a simple recipe and assembled all the ingredients.  A little box of plaster of Paris cost us $7 at Home Depot, so I don't know how cost effective this all is, though we are making use of our paints and learning how to make something for ourselves that we'd otherwise buy, usually made far away and shipped to us.  If this works, we will be able to supply ourselves with brilliant chalk, but also to gift it to our friends.

Directions:
  1. Mix 1.5 cups plaster of Paris in a disposable bowl (we use our cement mixing containers).
  2. Slowly add 3/4 cup of water.
  3. Add 2-3 tablespoons of tempera paint.
  4. Pour it into your molds (such as toilet paper tube with end sealed with strong tape).
  5. Let it dry.
  6. Use as awesome homemade chalk!
This is what happened.

Our ingredients list: containers with taped bottoms, plaster of Paris, tempera paint, water

adding and stirring (the water)


trying to make Hannah's favorite color (violet) with lots of powdered tempera paint

scraping the bowl clean after our first batch
Well, this was a great project to try together.  We made three batches and have enough plaster for a fourth.  Our first batch was as hard as a rock, though it works a bit after soaking in water.  The second batch was stirred too slowly and came out in fragile little pellets.  And our third batch works just right.  All the chalks came out in beautiful colors, though they all draw in white.  We will put together our fourth and final batch soon, this time adding more tempera paint, leaving Liam on my back in a carrier the entire time, and I will be the one to mix and stir quickly.  Once our plaster is used, I doubt we'll be making chalk again this year.  The kids loved making this at home and sharing it with neighbors.  Perhaps someday we will find a book involving chalk and throw a book club party with this project.

Have you made chalk?  Do you have any pointers for us?