Turn sugar and water into crunchy, rock-like crystals! Learn about chemistry, solutions, and crystallization by growing your own edible candy treats.

Tools

• pot
• spoon
• jar or glass

Materials

• water (1 cup / 240 ml)
• sugar (3 cups / 600 g)
• wooden chopstick (1)
• clothespin (1)

Safety

• Adult supervision is required for using the stove and handling boiling water.
• Be careful of hot surfaces and steam to avoid burns.
• Wash hands and tools before starting to ensure food hygiene.
• Adult supervision required for hot materials. Burn risk.
• Adult supervision required for sharp objects.
• Adult supervision required for children under 8.

Steps

1. Heat 1 cup of water in a pot on the stove until it starts boiling and bubbling.
2. Slowly pour in the sugar a little bit at a time, stirring with a spoon until the sugar dissolves and the water looks clear again.
3. Continue adding sugar and stirring until no more sugar will dissolve into the water (creating a supersaturated solution).
4. Remove the pot from the heat and let the sugar-water solution cool down to room temperature.
5. Dip the wooden chopstick into water and then roll it in a small amount of dry sugar to provide 'seed crystals' for the candy to grow on.
6. Place the chopstick inside the empty jar, ensuring it is suspended a few inches above the bottom and not touching the sides.
7. Secure the chopstick in place using the clothespin clipped to the rim of the jar.
8. Have a grown-up helper carefully pour the cooled sugar solution into the jar, leaving some space at the top.
9. Place the jar in a safe spot and wait 1 to 2 weeks for the crystals to grow and harden.
10. Once the crystals have grown to your liking, remove the chopstick and enjoy your rock candy!