science fair projects for 6th grade with hypothesis

Grades 6-12
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50 Interesting 6th Grade Science Fair Projects and Classroom Activities

Award-winning ideas and science demos on every topic.

Collage of 6th grade science fair projects, including a paper plane launcher and compost cups

Sixth grade science covers a wide variety of topics and varies depending on the curriculum. We’ve rounded up the best 6th grade science fair projects to inspire kids, as well as classroom science demos and activities that will grab their attention.

To make it easier to find what you’re looking for, we’ve rated all the projects and activities by difficulty and the materials needed:

Difficulty:

Easy: Low or no-prep experiments you can do pretty much anytime
Medium: These take a little more setup or a longer time to complete
Advanced: Experiments like these take a fairly big commitment of time or effort
Basic: Simple items you probably already have around the house
Medium: Items that you might not already have but are easy to get your hands on
Advanced: These require specialized or more expensive supplies to complete

Biology and Earth Science 6th Grade Science Fair Projects

Chemistry 6th grade science fair projects, physics and engineering 6th grade science fair projects, 6th grade science classroom demos and hands-on activities.

For students interested in anatomy, animals, geology, ecology, and more, these are the science fair projects they need!

Find the fastest way to ripen fruit

Difficulty: Medium / Materials: Medium

Need to ripen those bananas or peaches in a hurry? Do some research and then experiment to find the fastest way to safely ripen fruit without sacrificing flavor.

Clean up an oil spill

Sixth grade science student using a spoon to try to catch a puddle of oil floating on water

Learn why an oil spill is so devastating for wildlife and the ecosystem with this hands-on activity. Kids experiment to find the best way to clean up oil floating on water and rescue the animals affected by the spill. ADVERTISEMENT

Learn more: Oil Spill Cleanup at Kitchen Counter Chronicle

Explore new ways to filter water

Basic water-filtration systems are pretty simple, but they make terrific science fair projects. Experiment with different setups, and find a way to make safe drinking water for people who need it.

Shake it up with earthquake science

Two foam plates with structures built from wood craft sticks and putty on top

Difficulty: Easy / Materials: Basic

Build simple model structures, then experiment to see how the actions of earthquakes affect them. Do research into what engineers and architects build in earthquake zones, then perform an experiment to see if you can improve on their findings.

Learn more: Earthquake Science at Love To Know

Grow a better garden using hydroponics

Hydroponics is the hot new gardening trend, but is it really a better way to garden? Find out with a DIY hydroponics gardening setup, comparing the results with traditional container gardening.

Find out if chewing gum really helps improve test scores

One of the more popular 6th grade science fair projects answers the question: Does chewing gum affect test scores? You’ll be surprised by the results!

Create top-notch compost in a cup

Two plastic cups filled with compost and covered in plastic wrap

This is an easy science activity, and you can turn it into a science fair project by experimenting with different mixtures, layering, and conditions for your compost cups.

Learn more: Compost Cups at The Happy Housewife

Learn the best way to repel ants

Do you really need to use poisons to keep ants out of your home? Explore other possible solutions in this science project idea.

Simulate a tsunami and find ways to protect people

Build a model to simulate a tsunami, then come up with potential ways to minimize the damage future waves may cause.

Design a squirrel-proof bird feeder

Squirrels can be real pests at backyard bird feeders, and people are always trying to come up with new solutions to the issue. Can you be the one who finally solves this pesky problem?

Students who love to mix up chemicals and explore the results will enjoy these 6th grade chemistry science fair ideas.

Compare baking powder and baking soda

Baking powder and baking soda have similar names, but do they behave the same when used in a baking recipe? Bake up a few cakes and find out!

Devise a formula for creating the biggest soap bubbles

Soap bubble formulas vary, and some allow you to make bigger bubbles than others. What does it take to make the biggest bubble of them all?

Learn if tea and cola damage teeth

Three eggs next to containers of coffee, tea, and cola, with a permanent marker

Difficulty: Easy / Materials: Medium

Use eggshells to explore how various beverages can stain teeth in this classic 6th grade science fair project. (It also teaches important lessons about dental hygiene!)

Learn more: Teeth and Eggs at Education.com

Look for iron in your breakfast cereal

The human body needs iron to be healthy, and many breakfast cereal boxes boast that they contain it. Conduct a 6th grade science fair project to find out if cereals really contain all the iron they say they do.

Find the best way to clean up old coins

Pennies in small cups of liquid labeled coca cola, vinegar + salt, apple juice, water, catsup, and vinegar. Text reads Cleaning Coins Science Experiment. Step by step procedure and explanation.

Use common household items to make old oxidized coins clean and shiny again in this simple chemistry experiment. Form a hypothesis about which method will work best, then do some research to explain the results.

Learn more: Cleaning Coins Experiment at Gally Kids

Explore the effects of various sugars on yeast

Yeast needs sugar to grow, but does the type of sugar matter? And can you use sugar substitutes instead? This is a sweet way to find out!

Grow the biggest carbon sugar snake

Large carbon ash snake growing out of a pan of sand

Tinker with the formula to create the biggest carbon sugar snake possible! This is an engaging project that will wow other students too.

Learn more: Carbon Sugar Snake at KiwiCo

Determine whether soda has more sugar than juice

Which do you think has more sugar, a glass of Pepsi or one of orange juice? Boil away the water to find out in this 6th grade chemistry experiment.

Explore the properties of plastic made from milk

Making milk from plastic is actually pretty simple. Turn it into a science fair project by learning more about its strength, durability, and flexibility, and proposing a practical use for it.

Determine which type of juice has the most vitamin C

Vitamin C might not immediately cure your cold, but it definitely has health benefits. Does orange juice really have the most vitamin C? Conduct an experiment using an iodine titration method to learn the answer.

Calling all tinkerers! Build, create, and engineer a science fair project using physics principals.

Build a powerful paper-plane launcher

Sixth grade science student using a homemade launcher to launch a paper airplane

Here’s a cool 6th grade science fair project. Design and build a paper-airplane launcher that can fly a plane farther than anyone else’s.

Learn more: Paper Plane Launcher at Frugal Fun for Boys and Girls

Figure out the fastest way to cool a soda

Adding ice to a glass of soda cools it off, but it also waters it down. See if you can find a fast way to cool down soda while it’s still in the can or bottle instead.

Launch a bottle rocket higher or more accurately

A basic water-powered rocket isn’t that hard to assemble, but you can turn it into a bona fide 6th grade science fair project by playing around with the design. Figure out how to launch it higher, or change the trajectory to hit a certain target.

Identify the best insulating material

Insulating an item can prevent it from losing heat, like an insulated beverage bottle. What materials are the most effective insulators? How can you find out?

Drop parachutes to test air resistance

Card with text Which is the best parachute? Plastic, paper, cloth. Surrounded by pieces of fabric, plastic, and string.

Use the scientific method to test different types of material and see which makes the most effective parachute. This is an easy project that’s perfect for kids interested in design and engineering.

Learn more: Parachutes at Education.com

Discover which produce best powers a clock

Here’s one of those classic science fair projects that you can really customize to make your own. Try testing out a variety of fruits and veggies, or playing around with connecting several types of produce to see what happens. This inexpensive kit has all the supplies you need.

Engineer the strongest craft stick bridge

Difficulty: Medium / Materials: Basic

This is a classic science activity for the classroom, but it works well for 6th grade science fair projects too. Form a hypothesis about the strongest type of bridge design, then build your own models to test it out.

Assemble the best simple motor

A simple motor built from basic materials

Looking for an idea that’s impressive but not too complicated? Build your own simple motor! You only need a few special supplies, including insulated copper wire and neodymium magnets . Turn it into a true 6th grade science fair project by altering the variables to see if you can increase the speed, reduce the noise, or make other improvements.

Learn more: DIY Motor at Home Science Tools

Learn if room temperature affects candle burn rate

This is a simple experiment to conduct, and it’s inexpensive too. Burn birthday candles in a variety of temperatures to see if they burn faster in higher temps.

Determine how much money energy vampires are wasting in your home

So-called “energy vampires” use up energy even when they’re not in active use. And energy costs money. Determine how much energy is being wasted by energy vampires in your home, and figure out how much money you can save on an annual electric bill by getting rid of them.

Engage students with a live demonstration showing the concepts they’re studying. Even better, give them a chance to get hands-on and do the science themselves!

Assemble motorized tiny dancers

AA batteries with tiny wire figures twisted around them, with tutus added to look like ballet dancers

Build a homopolar motor to make little spinning wire dancers. It takes a little practice to get it right, but it’s a really fun way to learn about motors and energy.

Learn more: Tiny Dancers at Babble Dabble Do

Amplify your smartphone with basic supplies

Smartphone amplifier made from paper cups and a toilet paper tube

No Bluetooth speaker? No problem! Build your own from paper cups and a toilet paper tube. This is a 6th grade STEM challenge that’s sure to amaze kids.

Learn more: Cell Phone Speaker at The Mad House

Wear a gene bracelet

Bags of pony beads labeled with various traits like hair color and eye color

This is a neat way to talk about our genes. Have each student add pony beads to their bracelet to represent different traits. Then they can compare their differences and similarities. It’s likely that no two students will have the same bracelets!

Learn more: DNA Gene Bracelet at Pragmatic Mom

Make naked eggs

Sixth grade science student holding a raw egg without a shell

Students dissolve the calcium carbonate eggshell in vinegar and discover the membranes beneath that hold the egg together. It’s a unique and intriguing way to learn about acid-base reactions.

Learn more: Naked Egg at Making Memories With Your Kids

Experiment with naked eggs

Raw egg without a shell that has been dehydrated sitting next to a regular egg

Now, submerge those naked eggs in corn syrup and water to learn about osmosis. The eggs shrink or grow depending on the liquid they’re placed in. So cool!

Learn more: Naked Egg Experiments at Exploratorium

Send water traveling down a string

String running down into a glass partially filled with blue water

Explore the properties of cohesion and adhesion with this simple experiment using only water and cotton string. Expand the learning by trying the same experiment with different materials and liquids.

Learn more: Traveling Water at Rookie Parenting

Launch a two-stage rocket

The rockets used for space flight generally have more than one stage to give them the extra boost they need. This experiment uses balloons to model a two-stage rocket launch, teaching kids about the laws of motion.

Change the color of a liquid in an instant

Want to see your kids gasp in amazement? Perform the iodine clock reaction. You only need a few drugstore chemicals to change the solution from clear to dark blue faster than students can blink.

Levitate a Ping-Pong ball

Sixth grade student holding the cut off top of a plastic bottle with a straw attached. A ping pong ball is floating over the bottle top.

Kids will get a kick out of this experiment, which is really all about Bernoulli’s principle. You only need plastic bottles, bendy straws, and Ping-Pong balls to make the science magic happen.

Learn more: Bernoulli Ping-Pong Ball at Buggy and Buddy

Use a fidget spinner to understand inertia

Series of photos of a child holding a fidget spinner in action. Text reads 3 lights = highest inertia, decreasing inertia, 0 lights = lowest inertia

Learning about the laws of motion? This experiment uses a fidget spinner with three lights to show how mass and torque affect inertia.

Learn more: Fidget Spinner Inertia at Homeschool Momgineer

Build a heart pump model

Simple heart pump model made from plastic bottles, drinking straws, and modeling clay

Students gain a deeper understanding of the cardiovascular system when they construct a working model of a heart ventricle.

Learn more: Heart Pump Model at Tina’s Dynamic Homeschool Plus

Construct a pair of model lungs

Sixth grade student holding model lungs and diaphragm made from a plastic bottle, duct tape, and balloons

Build model lungs using a plastic water bottle and some balloons to learn more about the respiratory system. You can modify the experiment to demonstrate the effects of smoking too.

Learn more: Lungs Model at Surviving a Teacher’s Salary

Dissect an owl pellet

Sixth grade science student wear gloves, holding an owl pellet over a red tray

Dig into an owl’s regurgitated meals (it’s not as gross as it sounds!) to discover what their diet consists of. Owl pellets are readily available online, and kids will be intrigued by what they find.

Learn more: Owl Pellets at Gift of Curiosity

Study sound waves with a spoon

Sixth grade science student holding yarn strings to her ears and looking surprised

With just yarn and a metal spoon, learn how vibrations create sound, and explore the role of conductors.

Learn more: Spoon Sound Waves at KC Edventures With Kids

Make sparks with steel wool

Steel wool sitting in an aluminum tray. The steel wool appears to be on fire.

All you need is steel wool and a 9-volt battery to perform this science demo that’s bound to make their eyes light up! Kids learn about chain reactions, chemical changes, and more.

Learn more: Steel Wool Reaction at The Homeschool Scientist

Create a colorful cell model

Cell model made from a spiky pink hand sanitizer holder, labeled Our Bacterium Prokaryotic Cell

There are lots of cell model projects out there, but this might be one of the cutest ones we’ve seen! And it’s easier to assemble than you might think.

Learn more: Cell Model at Angelic Scalliwags

Extract DNA from a strawberry

It’s surprisingly easy to pull a strand of DNA from this sweet fruit. Teach your kids about genetics and DNA with this 6th grade science project that uses only basic household supplies.

Design a biodome

Model biodome made from plastic bottles and containers filled soil with and plants

There’s so much to learn in this 6th grade science project. Kids build a scale-model biodome to learn more about different environments and ecosystems, decomposition, the food web, and more.

Learn more: Biodome Project at Teach Engineering

Pull an egg into a bottle

Glass bottle with bowl holding three eggs, small glass with matches sitting on a box of matches, and a yellow plastic straw, against a blue background

This is another classic science demo that never fails to delight. Use the power of air pressure to suck a hard-boiled egg into a jar—no hands required.

Learn more: Egg in a Bottle at Left Brain Craft Brain

Make a pH indicator from a vegetable

Making a PH indicator from cabbage for 6th grade scientists.

Who knew such a simple material could be used to determine a substance’s acidity or alkalinity? Your students can explore acids and bases with this simple experiment.

Learn more: Red Cabbage Indicator at Compound Interest

Need supplies for your 6th grade science fair projects and activities? Check out these 24 Science Kits for Middle and High School That Make Hands-On Lessons Easy .

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This roundup includes interesting 6th grade science fair projects, as well as classroom demos and hands-on science activities to try.

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