Hot water actually freezes more quickly than cold water. Try freezing separate containers of hot and cold water to compare the results. [1] X Research source Feel free to try this out with other drinks like fruit juice or lemonade. If you use an ice cube tray or popsicle tray, you’ll be able to enjoy popsicles later on! Don’t use a glass container. The water will expand as it freezes and might break the glass. Breakage will also happen if you put a glass container filled with hot water in the freezer, so don’t ever try this.

Check to make sure the freezer is set to a temperature below 32 °F (0 °C), which is the freezing point of water. [2] X Research source

A tray of ice cubes will freeze in about 3 hours. A plastic water bottle might be frozen after 4 or 5 hours. Check back after 8 to 10 hours for a big plastic bowl of water. Sugary liquids like fruit juice will take longer than plain water to freeze. [4] X Research source

If you leave the ice at room temperature, it will melt and return to its liquid state after a while. An ice cube will melt in a matter of minutes!

This will encourage more sugar crystals to form from the liquid solution.

You’ve successfully created a solution, which is a combination of more than one compound. If you want to turn your crystallized sugar into edible rock candy, add a few drops of liquid food coloring and/or liquid food flavoring while the solution is still boiling. [9] X Research source

Wear oven gloves for protection and be careful not to splash the liquid. It’s essential to use a heat-safe container for this step. Any other glass may shatter.

If the top opening of the glass container is narrow, pinch the skewer with an alligator clip. The sides of the clip should rest on the rim of the container and keep the skewer in place. Another way to hold the skewer in place is to create a plus-shape out of 2 other skewers. Tape these 2 together and rest them over the rim of the container. Finally, tape the sugary skewer to the others so it remains upright.

If you notice the skewer crystals are getting close to other crystals growing along the sides of the glass container, gently move it away so the growth of your skewer crystals isn’t disturbed.

If you’d like to eat your rock candy, allow the skewer to drip-dry within another container. [14] X Research source Once the liquid has dried, you can enjoy your crystallized sugary snack!

Alternatively, this can be done in a saucepan on a stovetop, with adult supervision. Whole milk will work much better than 2% or skim milk because it has a higher fat content.

While stirring, you’ll notice hard clumps or curds forming in the milk. This will start to smell pretty weird. Don’t let this put you off, though. Keep stirring!

If you’re having a hard time picking the curds up with your spoon, tilt the container over a strainer above a sink to drain out most of the liquid. [17] X Research source

Use a few extra pieces of paper towel to pat the curds dry if the original sheets get too damp.

The ball of curds you’re holding is now casein plastic! When the milk curdled, the liquid separated from the fat solids and casein protein solids. The fat and protein bonded together in a polymer chain, making it a plastic.

Wear disposable gloves to prevent the dye from staining your hands. You can also try rolling it out flat and cutting out a shape using a cookie cutter. Whatever you try, make sure to finish everything within 1 hour of pulling the curds out of the milk. It will harden soon after that.

Once the plastic has completely hardened, you can draw on it with markers.

Keep stirring until you can’t see any more particles of salt in the water. This mixture is now a solution.

A metal baking pan, cake tin, or another shallow baking dish will work. Keep the container uncovered.

Through the process of evaporation, the liquid water will turn to gas while the dissolved salt will return to its solid state. [23] X Research source