Not only birds are born from egg shells. We eat eggs every day and tons of egg shells are thrown away. We thought it "mottainai", which means they have other ways to be used. Then we found that chalks can be made from egg shells.
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Step 1: What Do You Need?
- egg shells
- cellophane film
- a tea spoon of flour
- a tea spoon of hot water
- two morters(One of them has small grooves.)
- color powder(If you don't want to make color chalks, you don't nedd this)
- rubber band
- something to mix with
- straws(thick enough)
Step 2: Collect Egg Shells
Try to keep egg shells in large peaces because larger peaces are easier to be removed egg mambrane.
Step 3: Remove Egg Membranes
It's easier to remove egg membranes when they are wet.
Step 4: Boil the Egg Shells
Boil the egg shells. This process prevents egg shells from breeding various germs. It smells bad if you skip this step.
Step 5: Dry the Egg Shells
You can dry them quickly by heating in a microwave oven for 4 minutes.
Step 6: Powder Them in a Morters
First, make rough powder grinding in a morter which has small grooves.
Second, make them finer in another morter.
(First picture is the morter which has small grooves.)
Step 7: Mix Egg Shells Powder and Flour (and Color Powder)
Add a little bit of color powder if you want to make color chalks.
Step 8: Add Hot Water
Add hot water little by little while mixing. The mixed material will become like a clay.
Step 9: Stuff the Mixed Material Into Strows
Before you stuff it, make some tiny holes to release the air from the strows. Next, cover the bottom of the strows with cellophane film and rubber band. Then stuff the mixed material into the strows.
Step 10: Dry
Dry them completely. The time to dry depends on weather or humidity.
Step 11: Take Chalks From Strows
Take chalks from strows.
These look a little bit small and distorted, but these are chalks whatever others may say !!