Science fair project ideas for 9th graders to wow your friends, classmates, and teachers. Are you planning on what to create for your science fair project?
Here are some genius science fair project ideas for ninth graders.
These projects tackle different topics and concepts from food to environment, to physics and circuits, to chemistry and biology.
There will be one that suits your interest and get you thinking!
If you need some ideas for your upcoming science fair project, here is a list of different science fair project ideas for 9th graders.
This post is all about science fair project ideas for 9th graders.
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Science Fair Project Ideas for 9th Graders
Hydroponic Gardens
Are you interested in gardening?
If so, you can dive into this project with a new twist in gardening.
Planting without soil!
Yep, in this experiment, you will be able to explore topics like hydroponics, macronutrients, micronutrients, biochemical reaction, and photosynthesis.
You would need six plastic soda bottles, scissors, markers, a pack of seeds, paper towels, measuring spoons, bottled water, and more.
Through this project, you can investigate questions on the differences between micro and macronutrients.
You can also compare the growth rate of seeds in a regular environment versus in a hydroponic environment.
Are there any similarities or differences?
Check it out: Hydroponic Gardens
Potato Battery
Do you want to make a project related to circuits?
This science fair project involves a potato, yep you read it right, a potato.
Use a potato to try and create a circuit while measuring the voltage in either a series or parallel.
You will learn concepts including chemical reactions, currents, voltage, resistance, open circuit, and closed circuit.
The materials that you need include copper electrodes, zinc electrodes, alligator clips, potatoes, a ruler, paper towels, and more.
You can explore questions like how do open and closed circuits affect the potato battery?
Can you try this with other items instead of a potato?
This is a great project to try and show your friends and classmates.
Not only is it interesting, but also engaging to learn about circuits and power.
Check it out: Potato Battery
Mouse Trap Cars
Build a car with a mousetrap and cd wheels.
Try to build a mousetrap car that can travel the longest distance with stored energy.
Make the propeller with chopsticks, pipes, or anything you can think of.
These are one of the most common science fair project ideas for 9th graders to test how to limit friction and increase energy.
Some questions to inspect are which materials can make the mouse trap car go farther distances?
Does the shape or weight affect how fast or far it goes?
How does the placement of the mousetrap (on the sides or in the middle) affect the mousetrap car?
Check it out: Mouse Trap Car
Food Mold Experiment
If you want to try something icky for your upcoming science fair project, then this one will float your boat.
Test which food molds the quickest.
The materials you need include bread, cheese, strawberry, tomato, or another food of your choice, and paper plates.
Record results by snapping a picture each day to see any changes.
Make sure you store this in a cabinet or somewhere where younger children or siblings won’t be able to reach it.
This food mold project might have been done previously when you were younger, but you can take further steps to advance this project.
Check out what preservatives can slow down the molding of foods.
If you have a lab at school, see if you can look at your mold growth under microscopic lenses.
Questions you can explore are why does food grow mold?
Should food grow mold or should it contain preservatives to prevent mold? Why or why not?
Check it out: Food Mold Experiment
Popping Boba
After that icky food mold experiment, here is a change of scenery-juicy, popping boba.
Try this project if you want to experiment with how sodium citrate and differing pH affect how different foods go through spherification.
Some concepts that you will explore include spherification, chemical reaction, molecular gastronomy, sodium alginate, and calcium chloride.
The materials that you need are tap water, measuring cups, plastic wrap, sodium alginate, calcium chloride, and more.
You can explore questions like what changes with sodium alginate and calcium chloride during spherification?
What process occurs in this experiment?
Check it out: Popping Boba
Heat Conduction Experiment
You may have previously created this type of experiment in middle school.
However, you can make this project more complex and innovative by adding more conduction methods.
Try to test how long water stays warm in aluminum, copper, stainless steel, plastic, glass, etc.
You can easily create this experiment with hot water, a thermos, and cups with different materials.
Measure the temperature after various increments and compare which material holds heat longer than others.
You can also try keeping a lid on versus having the lid taken off.
How much do these variables affect the water temperature?
Check it out: Thermal Insulation
Pressure Water Bottle Rockets
Learn more about Newton’s laws of motion through this simple water bottle rocket.
You would only need a soda bottle, water, pump, launcher, and tube to create this project.
This is a very interesting science fair project for 9th graders and especially fun in the hotter months!
You can ask additional questions like what alterations can you add to shoot the rocket higher?
Does the liquid (water versus sparkling water) affect the speed the rocket shoots up?
There are many versions of this online and you can tweak it to suit your preferences.
Check it out: Bottle Rockets
Marble Roller Coaster
Photo by JC Dela Cuesta on Unsplash
This is a classic high school science fair project for 9th graders.
Test how fast you can make a roller coaster with pipes at a certain height.
Try out how different loops, heights, and starting points can alter the speed or time of the marble on the roller coaster.
Explore the different concepts of kinetic, potential, and conservational energy.
You can also try out more questions like what materials can you add to make the roller coaster faster?
Do the angles of the loops make the roller coaster go faster or slower?
Check it out: Marble Roller Coaster
Marshmallow Catapult
Photo by Rebecca Freeman on Unsplash
Another fun science fair project for 9th graders is this marshmallow catapult.
Explore how to make a catapult to propel marshmallows as far as possible.
There are simple versions of this with spoons, popsicle sticks, and rubber bands.
However, you can make this project more advanced by testing out different supplies.
I built mine before with PVC pipes and got extra credit for shooting it in a trash can.
Even though mine did not shoot the farthest, it was able to shoot accurately which earned me a high grade with extra credit!
You can build your own with everyday supplies or move up the levels with other materials that you can use.
Check it out: Marshmallow Catapult
Color Absorption
Start a project on testing how the color of an object affects the amount of heat it takes in when exposed to light.
This is a low-cost project that requires minimal equipment of glass jars, colored construction paper, scissors, tape, water, a thermometer, and a heat lamp.
Learn more about concepts like absorption of light, the reflection of light, and the electromagnetic spectrum.
Explore questions like how different light bulbs work and how color affects heat absorption.
You can also test out other questions like which colors are best in the cold?
How long does it take to absorb heat and what other variables may affect the time it takes?
Check it out: Color Absorption
Breakfast Consumption Experiment
Photo by Rachel Park on Unsplash
Another cool science fair project for 9th graders is conducting an experiment to determine how important breakfast is to academic performance.
This project gives you more room to create surveys and includes variables.
You will need to have a test to evaluate the performance of students who ate breakfast versus those who didn’t.
Inspect how food may or may not affect performance.
You should also record the results and compare them.
Create graphs, tables, and data to prove your point.
You can also explore additional questions like how full should you be to reach optimal performance?
How long should you eat breakfast beforehand to perform your absolute best?
Check it out: Breakfast Consumption
Design On Eyes: Influence of Packaging
Photo by Studio Blackthorns on Unsplash
Does the design of packaging affect how people pick products?
You can try this experiment with different age groups and record the results.
This project requires materials like a printer, computer, design software, test subjects, glue, and scissors.
You will need to design several packaging images and paste them on blank boxes.
Then have your test subjects pick which ones they want.
Have them rank the packaging and record the results to compare at the end.
You can explore questions like does the placement of text, color, or images affect how others pick a product?
Which colors/designs are more popular and appealing to different age groups and what could be the reason behind them?
Check it out: Influence of Packaging
Solar-Powered Water Filter
Photo by Michael Burrows
Do you ever wonder if you can filter seawater to drink?
Well, this project is for you if you are interested in environmental and ocean topics.
Learn concepts like evaporation, water vapor, the reflection of light, absorption of light, and desalination.
Answer questions like what variables affect how fast something evaporates. Or why is there condensation when water gets hot?
This project does require more supplies than other projects.
You will need plastic cups, beakers, thermometers, straws, washers, rubber bands, construction paper, containers, and more.
And you can also explore additional questions like what other types of water can you desalinate?
What can you alter to make the desalination faster or more accurate?
This is a pretty interesting project that you can write about and show to your friends!
Check it out: Solar-Powered Water Filter
Make Your Own
If these science fair project ideas for 9th graders aren’t enough, why not create your own?
You just need to brainstorm a question or problem that you want to test.
What materials do you need?
What variables are involved?
Can you replicate it and record the results?
Make sure you can answer all the questions and implement them in your science fair project.
This post was all about science fair project ideas for 9th graders.
