The best examples of growing crystals: 3 fun home experiments kids love

Let’s start with the heart of this guide: three reliable, kid-friendly crystal projects. These are the best examples of growing crystals: 3 fun home experiments you can run with common supplies and a little patience.

Experiment 1: Sugar rock candy – the tastiest example of growing crystals

If kids want an example of a crystal they can actually eat, rock candy is your star. It’s just sugar crystals that slowly grow on a stick or string as water evaporates.

Basic idea in kid language:
You pack so much sugar into hot water that the water can’t hold it all forever. As the water cools and then slowly evaporates, the extra sugar has to go somewhere, so it “sticks” together in neat patterns called crystals.

What you’ll need

• Granulated sugar
• Water
• A clean glass jar or tall glass
• A wooden skewer or piece of cotton string
• Clothespin or tape (to hold the stick in place)
• Food coloring and flavoring extract (optional but fun)

Simple steps
Make this conversational and relaxed with kids:

Start by boiling water and stirring in sugar a little at a time until it simply won’t dissolve anymore. That’s your supersaturated solution. Let it cool for about 10–15 minutes so it’s hot but not boiling. Meanwhile, dip your skewer in water, roll it in sugar, and let it dry. Those tiny sugar grains become “seed crystals” that give new crystals a place to start growing.

Pour the warm sugar solution into your jar, add a drop or two of food coloring if you like, then lower your sugared stick into the middle. Use a clothespin or tape on top of the jar to keep the stick from touching the sides or bottom. Now you wait.

Within a day, you should start to see little bumps of sugar forming. Over 5–7 days, those bumps grow into big, chunky rock candy crystals.

Fun variations and extra examples
These give you more examples of growing crystals: 3 fun home experiments style activities using the same basic idea:

• Try brown sugar for caramel-colored crystals.
• Use different food colors for a “crystal rainbow” on separate sticks.
• Compare warm room vs. cooler room to see where crystals grow faster.
• Try a no-food-color batch and a colored batch to see if color changes growth.

This rock candy activity lines up well with how real mineral crystals form from cooling magma or evaporating water in nature. The U.S. Geological Survey has kid-friendly information on crystals and minerals here: https://www.usgs.gov/special-topics/water-science-school/science/crystals

Experiment 2: Salt and Epsom salt – fast, sparkly examples of growing crystals

If you want a faster example of growing crystals (and you’re not interested in eating the results), salt and Epsom salt crystals are fantastic. They’re cheap, safe with supervision, and they grow into beautiful shapes.

Table salt crystal gardens

Regular table salt (sodium chloride) grows into neat, cube-shaped crystals. Kids can actually see the tiny cubes if they look closely with a magnifying glass.

You’ll mix hot water with salt until no more will dissolve. Then you pour that solution into a shallow dish or small jar and leave a piece of rough material in the middle: a rock, a bit of cardboard, a piece of sponge, or even a pipe cleaner. As water evaporates, salt crystals begin to grow on the surfaces.

This is a real example of how salt flats form in nature when salty lakes dry up and leave sparkly white crusts behind.

Epsom salt crystal “forests”

Epsom salt (magnesium sulfate) behaves a little differently. Instead of cubes, it often forms needle-like or feathery crystals that can grow more quickly than table salt.

Here’s how to turn it into another one of your examples of growing crystals: 3 fun home experiments style projects:

Dissolve Epsom salt in very warm water (not boiling), again adding salt until it stops dissolving. Pour this into a shallow dish. Add a few drops of food coloring in different spots, then slide the dish into the refrigerator. In a few hours, you’ll often see thin, sparkly crystals spreading across the bottom, almost like frost.

Extra variations and comparisons
To create more examples include:

• Compare table salt vs. Epsom salt in the same style of dish.
• Try one dish in the fridge and one on the counter to compare temperature effects.
• Use different colors in different dishes to see if dye affects crystal shape.
• Place black paper under a clear dish so the white crystals stand out.

For older kids, you can connect this to real crystal science. The Royal Society of Chemistry has accessible explanations of crystal structures and shapes: https://edu.rsc.org/resources/crystals

Experiment 3: Borax crystal shapes – dramatic, kid-favorite examples

If you’re looking for the most dramatic examples of growing crystals: 3 fun home experiments, borax crystal ornaments are hard to beat. They grow quickly, they’re eye-catching, and you can shape them into hearts, stars, snowflakes, or initials.

Safety note: Borax is a common laundry booster, but it should not be eaten, inhaled, or rubbed into eyes. Adults should handle the powder, and kids should wash hands after touching finished crystals. For health and safety questions about household chemicals around kids, you can explore general guidance on Mayo Clinic: https://www.mayoclinic.org/healthy-lifestyle/childrens-health

How it works

You twist pipe cleaners into shapes—snowflakes, hearts, letters—and hang them in a jar. Then you pour in a hot, supersaturated borax solution. As the water cools, borax comes out of solution and forms crystals on the pipe cleaners.

Within a few hours, you’ll see a dusting of crystals. By the next day, you’ll have a sparkling, solid crystal ornament.

Ideas to try
To multiply your examples of this experiment:

• Make seasonal decorations: crystal snowflakes in winter, flowers in spring.
• Compare thick vs. thin pipe cleaner shapes to see which collect more crystals.
• Test different solution strengths (less borax vs. more borax) to compare growth.
• Use colored pipe cleaners vs. plain white and see how color shows through.

This experiment is a great example of nucleation and crystal growth on a surface. In real research labs, scientists grow crystals on tiny surfaces to study materials, medicines, and more. The National Institute of Standards and Technology (NIST) has approachable material on crystal structures and materials science: https://www.nist.gov/topics/materials-science

More real examples of growing crystals at home

Once kids see these first examples of growing crystals: 3 fun home experiments, they usually want more. Here are additional ideas you can spin off from the same basic science.

Alum crystals for big, clear “gems”

Alum (often sold in the spice aisle for pickling) can grow into large, clear crystals that look like fake gemstones. You mix a hot alum solution, add a tiny “seed” crystal tied to a string, and let it grow for several days. This is a great example of slow-and-steady crystal growth.

Copper sulfate crystals (for older kids with supervision)

Copper sulfate can grow dazzling blue crystals, but it is not safe for young children to handle freely or ingest. This one is best reserved for teens, with gloves and careful supervision. Because of the safety factor, many families skip this at home, but it’s a real example you might see in school labs.

Instant “crystal” look with baking soda stalactites

Technically, these are more like crystal deposits than big individual crystals, but kids love them. You tie a string between two cups of baking soda solution and watch as deposits build up along the string, like mini cave formations.

All of these give you more examples of growing crystals beyond the original 3, while still relying on the same idea: a saturated or supersaturated solution that slowly lets solids come back out in an organized pattern.

Helping kids connect these examples to real-world science

Kids often think crystals are just “pretty rocks.” These examples of growing crystals: 3 fun home experiments are a chance to show them that crystals are everywhere—from snowflakes to table salt to smartphone screens.

Here’s how to build that bridge in simple language:

• In nature: Quartz, amethyst, and many gemstones are natural crystals. They form in hot, underground spaces or in cracks where mineral-rich water cools and evaporates.
• In the kitchen: Sugar and salt are everyday crystals. Under a magnifying glass, they already have crystal shapes before you ever start an experiment.
• In technology: Many electronic devices rely on crystalline materials, like silicon chips and quartz in watches.

The American Chemical Society has kid-focused resources on crystals and chemistry that can back up your explanations: https://www.acs.org/education/resources/kids.html

Tips for success with these examples of growing crystals at home

If you’ve ever tried a crystal experiment that just…did nothing, you’re not alone. These tips help your examples of growing crystals: 3 fun home experiments actually succeed.

Start with very hot water
Hot water can hold more dissolved material. That’s what makes a solution “supersaturated.” If you don’t use hot enough water, you may not get many crystals.

Keep everything still
Bumping the jar, moving it around, or stirring after setup can break tiny forming crystals and slow growth.

Give it time
Some crystals show up in hours (Epsom salt, borax), but the best rock candy can take a week. Turn it into a daily observation habit: kids can sketch what they see each day.

Control temperature as a variable
Try one jar in a warm spot and one in a cooler spot. Ask kids: in these examples of crystal growth, which environment helped more crystals grow? You’re quietly teaching about variables and fair tests.

Use simple science talk
You don’t need fancy language. Focus on three big ideas:

• Dissolve: The solid seems to disappear in water.
• Saturated: The water can’t dissolve any more solid.
• Crystals: The solid comes back out in a neat, repeating pattern.

Why these are some of the best examples of growing crystals for kids

Parents and teachers keep coming back to these examples of growing crystals: 3 fun home experiments because they hit a sweet spot:

• They use inexpensive, easy-to-find materials.
• They show visible progress over time (which kids love tracking).
• They’re flexible enough for simple fun or deeper science discussion.
• They can be adapted for ages—from preschoolers just observing to middle schoolers designing their own variables.

If you want to turn this into a mini science unit, you can:

• Have kids keep a crystal growth journal with dates, drawings, and notes.
• Compare at least two different crystal types (sugar vs. salt, borax vs. Epsom).
• Ask kids to predict which examples include the fastest growth, the biggest crystals, or the most colorful results.

By the time you’ve tried a few of these, you’ll have a whole gallery of homemade crystals—and kids who understand that science is something they can literally grow on the kitchen counter.

FAQ: common questions about examples of growing crystals at home

Q: What are some easy examples of growing crystals for beginners?
A: The easiest examples of growing crystals: 3 fun home experiments are sugar rock candy, table salt crystals in a shallow dish, and borax crystal ornaments on pipe cleaners. All three use hot water and a lot of dissolved solid, then rely on cooling and evaporation to grow visible crystals.

Q: Which example of a crystal experiment grows the fastest?
A: Epsom salt and borax crystals usually grow the fastest. You can often see clear growth in a few hours and dramatic results overnight. Sugar rock candy and large alum crystals take longer but can grow bigger, chunkier crystals.

Q: Are these examples of crystal experiments safe for young kids?
A: Sugar and table salt experiments are generally safe with supervision, especially since the materials are food-grade. Borax and alum should not be eaten and should be handled by an adult or older child with clear rules about not touching eyes or mouths. Always supervise around hot water and glass containers.

Q: Can I use these examples of growing crystals for a science fair project?
A: Absolutely. These are classic science fair topics. To turn them into a project, compare variables: different temperatures, different concentrations, or different substances (sugar vs. salt). Record measurements like crystal size, time to first crystals, or total number of visible crystals.

Q: What if my crystals don’t grow at all?
A: If none of your examples of crystal experiments work, common issues include: water not hot enough, not enough solid dissolved (solution not saturated), or the setup being disturbed too often. Try again with hotter water, more solid, and a quiet spot where the jar won’t be bumped.

Q: Are there real examples of crystals like these in nature?
A: Yes. Rock candy is a good model for quartz and other mineral crystals that form as hot, mineral-rich fluids cool. Salt crystal gardens are similar to salt flats where salty lakes evaporate. Needle-like Epsom salt crystals resemble some natural mineral habits. These home experiments are simplified examples of how nature builds crystals over long periods of time.