To grow rock candy takes about a week. Have Cub Scouts start their rock candy for one meeting and then have a place to keep the candy safe for a week while the crystals form.
Before the meeting:
- Practice growing a crystal using the directions below. This will allow you to share the finished crystal.
- Clean the glass jars thoroughly with hot water.
- Prepare sugar water mixture.
- Place the 4 cups of water in a medium-sized pan and bring it to a boil. Begin adding the sugar, 1 cup at a time, stirring after each addition. You’ll notice that it takes longer for the sugar to dissolve after each cup you add. Continue to stir and boil the syrup until all of the sugar has been added and it’s completely dissolved, this should be about 10 cups. The solution should be thick and the last cup of sugar you add should stay on the surface and the sugar and water mixture is thick. Add additional cups of sugar if needed. Remove the pan from the heat.
- If you’re using colors or flavorings, add 2 to 3 drops of food coloring and stir it in to ensure an even, smooth color. When using an extract, add 1 teaspoon of the extract; for flavoring oils, only add ½ 14 teaspoon. Make sure you don’t stand right in front of the pan because the scent can be very strong as it rises in the steam.
- Allow the sugar syrup to cool for 20 to 30 minutes.
- Set up meeting space with room for Cub Scouts to do their project. Cover the table.
During the meeting:
- Share with Cub Scouts that they will be making a crystal that they can eat. Show them the finished product and then lead them through the experiment.
- Wet each wooden skewer water and roll it in granulated sugar. This base layer gives the sugar crystals something to grab when they start forming. Set these aside to dry while you prepare the sugar syrup.
- Pour the syrup into the clean, prepared jars.
- Lower one sugared skewer into each jar until it hangs about 1 inch from the bottom.
- Carefully place your jar in a cool place, away from harsh lights, where it can sit undisturbed. Cover the top loosely with plastic wrap or a paper towel.
- Let Cub Scouts know that it will take a couple of days but they should start to see sugar crystals forming within two to four hours. If you see no change after 24 hours, try boiling the sugar syrup again and dissolve another cup of sugar into it. Then pour it back into the jar and insert the skewer or string again. They may do this with adult supervision.
- Allow the rock candy to grow until it is the size you want. Don’t let it grow too large; otherwise, it might start growing onto the sides of your jar.
- Note that a top layer of crystal will form. This is OK. Once the candy has reached the desired size, break that top layer of crystal up with a fork before removing the candy.
- Transfer the rock candy to an empty jar or glass (keep the clothespins to balance it) and allow it to dry for one to two hours.
- Enjoy your rock candy.
