Chemistry Experiments for Kids That Teach Real Science

Chemistry sounds like something that belongs in a high school lab with goggles and beakers, but some of the best chemistry experiments for kids use nothing more than baking soda, vinegar, and a few kitchen staples. That accessibility is exactly why chemistry is such a good fit for elementary students: they get to watch matter change right in front of them, and the wonder does the teaching. The trick is choosing experiments that go beyond the wow factor and actually build a concept.

This post rounds up classroom-friendly chemistry experiments for grades 2 through 5, organized by the science each one teaches, with tips for turning them into real investigations instead of just demonstrations.

Why Do Chemistry Experiments With Kids?

Chemistry has a reputation for being hard and abstract, and that reputation starts early. Hands-on experiments flip it. When students mix two things and watch a gas bubble up or a color change, chemistry stops being a scary word and becomes something they can see and explain. That early confidence matters more than any single fact they memorize.

The experiments below teach a core idea from the elementary matter standards: matter can change, some changes make a new substance, and some do not, and mixing and dissolving follow rules students can discover. The American Chemical Society’s Adventures in Chemistry is a good source of safe, kid-friendly activities if you want even more.

Chemistry Experiments That Show a Chemical Reaction

These experiments make a new substance, which is the definition of a chemical change. Have students watch for the signs: bubbles, a color change, heat or cold, a new smell, or a change they cannot undo.

• Baking soda and vinegar. Put a spoonful of baking soda in a cup and pour in vinegar. It fizzes as the two react to make carbon dioxide gas, a new substance. Do it in a sealed bag to trap the gas and show it is real matter.
• Milk into plastic. Warm a cup of milk, stir in a few spoonfuls of vinegar, and rubbery curds form. Strain, press, and mold them, and students have made a simple plastic called casein from a reaction.
• A rusting nail. Set a steel nail in a little water and check it over several days. The reddish rust that forms is a new substance, and it will not scrub back to shiny metal.
• Cleaning pennies. Soak dull pennies in a little vinegar with a pinch of salt for a few minutes. The acid removes the dark oxidized layer and the pennies shine, a reaction students can watch and time.
• A browning apple. Cut an apple and leave the slices out to brown as they react with the air. Dip a few slices in lemon juice to show how it slows the reaction down.
• Red cabbage indicator. Soak chopped red cabbage in warm water to make a purple liquid. Add lemon juice, and it turns pink; add baking soda, and it turns blue-green, revealing acids and bases through a color change.
• A cold reaction. Stir baking soda into a cup of water with a crushed antacid tablet or citric acid, and have students feel the cup turn cold. The reaction absorbs heat, which surprises students who expect every reaction to be warm.
• Elephant toothpaste (teacher demo). Warm water, dish soap, and a little yeast added to hydrogen peroxide erupt into warm foam as oxygen is released. Keep this one teacher-led, and let students predict and explain what the foam is.

These are the heart of a chemical change unit. My post on physical and chemical changes explains the difference in kid-friendly terms, and my examples of physical and chemical changes post has more you can sort with students.

Chemistry Experiments With Mixtures and Solutions

Not every chemistry experiment makes a new substance. These explore how things mix and dissolve (a physical change), and they are some of the most visually satisfying activities you can run.

• Skittles rainbow. Arrange candy in a ring around the edge of a white plate, then pour a little warm water into the center. The colors dissolve and spread inward, showing dissolving and diffusion.
• Walking water. Line up cups of colored water with empty cups between them, and bridge each pair with a folded paper towel. Over a few hours, the water climbs the towels, and new colors appear in the empty cups.
• Marker chromatography. Draw a thick band of washable marker near the bottom of a coffee-filter strip, then dip just the tip in water. As the water rises, the color separates into the different colors that were mixed to make it.
• Rock candy crystals. Stir as much sugar as will dissolve into hot water, pour it over a string or stick in a jar, and wait about a week. Sugar crystals grow as the water cools and evaporates, showing a saturated solution and crystallization.
• Salt water evaporation. Dissolve salt in warm water and leave the dish in a sunny spot. As the water evaporates, the salt reappears, showing that dissolving is a physical change and that the salt never left.
• Separate a mixture. Give students a cup of mixed sand, salt, and water and challenge them to separate the parts. Filtering catches the sand, and evaporating the water leaves the salt, a mini engineering-and-chemistry task.
• Oil and water. Shake oil, water, and a drop of food coloring in a jar and watch them separate into layers. Add a squirt of dish soap and shake again to see how it breaks up the layers.
• Dissolving race. Drop a sugar cube in cold water and another in hot water, and time which disappears first. Changing only the temperature makes this a real experiment about how fast things dissolve.

Chemistry Experiments With Physical Changes and States of Matter

These experiments change a material’s form without making anything new, which makes them a clear contrast to the reactions above.

• Ice cream in a bag. Seal cream, sugar, and a little vanilla in a small bag, put it inside a bigger bag of ice and salt, and shake for several minutes. The salt lowers the freezing point, and the liquid freezes into ice cream.
• Make butter. Shake cold heavy cream in a sealed jar for several minutes until the fat clumps into butter. It is a physical change that students can spread on a cracker.
• Homemade lava lamp. Fill a bottle mostly with oil, add water and food coloring, then drop in a piece of antacid tablet. Colored bubbles rise and fall, showing density and that oil and water do not mix.
• Melt and refreeze. Time an ice cube as it melts on a plate, then put the water back in the freezer. Matter changes state but stays the same substance, so you can reverse the change.
• Crystal shapes. Dissolve borax in hot water, hang a pipe-cleaner shape in the jar, and leave it overnight for crystals to form. An adult handles the borax while students watch crystals grow from a solution.

How to Turn a Chemistry Experiment Into a Real Investigation

The difference between a fun demo and real science is what students do with it. A few moves turn any of these into an investigation:

• Predict first. Before you mix anything, have students write or say what they think will happen and why.
• Observe closely. Ask students to record what they see, hear, and smell, and to watch for the signs of a chemical change.
• Explain with evidence. Have students decide whether a new substance formed and back it up with what they observed. This is a natural fit for claim, evidence, reasoning.
• Change one thing. Try warm water versus cold, or more vinegar versus less, so students test a variable instead of just watching once.

That last step is where the real thinking lives.

A Note on Safety

Every experiment here uses safe, common materials, but a few habits keep it smooth: read through each one first, keep tasting to the food-based activities like butter and ice cream only, wipe up spills right away, and reserve anything with heat, flames, or hydrogen peroxide for a teacher-led demonstration. Goggles are a nice touch and help students feel like real scientists. If you want even more tested activities to pull from, Science Buddies has a large library of vetted STEM experiments.

Frequently Asked Questions

Bringing It All Together

Chemistry experiments for kids work best when the wonder leads to a question. Pick a few that match what you are teaching, whether that is reactions, mixtures, or physical changes, and turn each one into a predict, observe, and explain routine. Students walk away not just having seen something cool, but able to say what happened and why, which is the whole point of doing science.

Want investigations that are ready to teach? My chemical reactions science stations for 5th grade walk students through hands-on chemical change investigations with recording sheets, and my reversible and irreversible changes sort is a quick way to practice classifying changes in 2nd and 3rd grade, all aligned to NGSS.