Pour 2 cups of sugar and 1 cup of water into a saucepan.

Stir the mixture over medium heat until the sugar disappears.

Add 1 more cup of sugar, a little at a time. Keep stirring until the sugar disappears.

Turn off the heat. Take the saucepan off the heat and let it cool for 25 minutes.

While you are waiting, clean the paper clip with soap and water. Tie one end of the string to the pencil. Tie the other end to the paper clip.

Have an adult pour the mixture into the glass. (It helps to use a funnel or do this over a sink.)

Place the pencil over the top, letting the paper clip fall into the mixture. Let it sit on a counter for 12 hours.

Remove the pencil and string and set it aside. What do you see? (Sugar isn't a mineral, but it forms crystal shapes just as minerals do.)

Reheat the sugar mixture in a pan. Keep stirring until the sugar disappears.

Take the saucepan off the heat and let it cool for 25 minutes.

Have an adult pour the mixture into a glass. This, time, add a few drops of food coloring. Stir it well so that the color mixes throughout the liquid.

Place the pencil over the top of the glass, letting the paper clip fall into the mixture. Let is sit for 12 more hours.

Remove the pencil and set it aside. What happened to the crystals? How would you describe the crystals that formed? Are they different from the first crystals you made?

If you want to make your rock crystals bigger, keep repeating the steps above.

Before you eat your rock candy, be sure to cut off the paper clip.

As you can see, rock candy is really just a bunch of sugar crystals. Enjoy your tasty treat!