Life in New Zealand has changed rapidly. Our borders are closed, domestic travel restricted, our schools and shops closed, and we are asked to remain at home in order to restrict the spread of Covid-19. Cars are now to be used only for essential travel (the doctor, pharmacy, or supermarket) and people may only leave their house to walk nearby. Social distancing is everything.

Our big field trip for today was walking to the top of the driveway and drawing pictures that the kids in the houses nearby can see from their windows. Creating chalk, with a few simple ingredients from the supermarket, has been both art and science. It’s also a way to share a little love and kindness with the community around us.

Why not bring a little colour to yours?

How to make home made chalk

Ingredients

• Cornflour
• Water
• Food colouring
• Cardboard tubes
• Waxed paper / baking paper
• Scissors
• Sellotape or rubber bands

Note: Alternative ingredients include plaster of paris + tempera paint, or a 1:2 ratio of very finely crushed eggshell + flour.

Directions

1. Prepare your moulds. Toilet paper rolls are a good size; I find a bread knife does a good job of sawing longer cardboard inner tubes into parts.
2. Cover the bottom of your cardboard tubes with waxed paper and tape / elastic band into place. You then want to roll more waxed paper and slot it inside (you may need to trim to size).
3. Pour cornstarch into a bowl and then add food colouring of your choice. Slowly add water and mix well. You want to add just enough water to create a very thick [viscous] mixture.
4. Pour or spoon the mix into your moulds.
5. Pop into a hot water cupboard (or somewhere warm to dry). You want as much of the water to evaporate as possible to dry before use (about 24-48 hrs).
6. You can then removed from the moulds and let the kids have fun!

Tip

If you add too much water then it will have difficulty drying (and remaining contained within the moulds). Never fear! Treat it as a chemistry and physics lesson all-in-one for the kids. You have just created a non-Newtonian fluid 🙂 You can take your ooblek outside for messy play fun with the kids. Pour it into your hands and watch how it becomes a solid if you clench your fist but magically liquefies if you release the pressure!