Watching crystals form on a stick in a jar is fascinating especially to kids no matter how old or young they are. When those crystals so happen to be the sweetest thing you can eat the fascination level increases still more.
I was about 12 when I first tried this experiment. It was not a success. In fact, it was a complete failure. The biggest factor dooming me to failure was not using enough sugar. If I had added a tea bag it might have been a fairly sweet glass of tea but I was no where near the saturation level.
It actually is quite an easy and fun experiment and kids love to check on their crystals daily. In fact, the crystals will begin to form almost immediately. After a week you will have a fairly decent chunk of sugar crystals like we did.
All you need is sugar and water and if you want to flavor the candy you can use strawberry flavoring, mint, coconut flavoring, or vanilla. We opted for coconut and strawberry and the reviews as to the best flavor where split.
Here is what you need to do:
Bring one cup of water to a boil.
Add three cups of sugar to the boiling water and bring back to a boil.
Stir until all the sugar is dissolved. Add a drop or two of food coloring if you wish and a little flavoring if you wish.
Pour syrup into a quart size jar making sure to omit any undissolved sugar crystals that may be hiding in the bottom of the pan. Allow the syrup to cool for 20 minutes.
Once the syrup has cooled 20 minutes you may put the stick into the jar. Adjust it to be about an inch from the bottom of the jar. It should not rest on the bottom. The lid will help keep dust out of the jar. Set the jar aside and check back every 24 hours. If sugar begins to form on the edge of the jar or on the surface of the syrup remove the stick and pour into a fresh jar. The idea is to keep the formation on the stick and not on the jar.
You will have rock candy in 7 to 10 days. Pull out your stick with the crystal formations and allow to dry for a couple of hours.
Any leftover syrup can be poured into a shallow pan and left out overnight to allow sugar crystals to form for more rock candy. It still tastes like rock candy but jut is not attached to a stick.