Ninth Grade Science Experiments (Page 60)

Musical Bottles

STEM Activity

1

2

3

4

5

19 reviews

Have you ever blown across a bottle's top and made a pleasant, resonant sound? If so, have you wondered how that note is made exactly? The exact note you hear depends on the resonant frequency of the air in the bottle. Musical instruments like ocarinas operate based on a similar principle. In this science activity, you will use bottles to investigate how the volume of the air in the bottle affects the pitch of the note that it makes. Read more

No Pain, Lots of Game

Science Fair Project Idea

Scientific Method

You might have heard the expression, "Take two aspirin, and call me in the morning." What if instead a doctor said, "Play two video games and call me in the morning"? Would you be shocked? Or think it was time for a new doctor? In this science fair project, you'll investigate whether video games, and other forms of mental distraction, have the power to relieve pain. Read more

Predicting Future Water Quality with Machine Learning

Science Fair Project Idea

Scientific Method

Understanding the water quality of our rivers, streams, and lakes is critical for maintaining healthy ecosystems and sources of drinking water. Dissolved oxygen is one key water quality measurement that impacts aquatic life. But how can we predict how water quality might change in the future so we can intervene to keep our water healthy? With machine learning! In this project, you will gather water quality data for a location of your choice and use a random forest model to predict future… Read more

Rocking the Boat

Science Fair Project Idea

Scientific Method

When a ship rocks back and forth, it can make people seasick. Even worse, it can make it dangerous for jets to land on aircraft carriers. For these reasons and many others, it's important for engineers to design bilge keels (or fins) to keep boats from rolling back and forth. Become an engineer for a day and discover the best way to keep from rocking the boat in this engineering science fair project! Read more

Rubber Band Elasticity and Temperature

Science Fair Project Idea

Scientific Method

Many materials expand when heated and contract when cooled. What do you think will happen to the elasticity (stretchiness) of a rubber band when it is heated or cooled to various temperatures? Read more

Rubber Bands for Energy

STEM Activity

1

2

3

4

5

38 reviews

If you've ever been shot with a rubber band then you know it has energy in it—enough energy to smack you in the arm and cause a sting! But have you ever wondered what the relationship is between a stretched rubber band at rest and the energy it holds? The energy the rubber band has stored is related to the distance the rubber band will fly after being released. So can you guess one way to test how much energy a stretched rubber band contains? Read more

Rubbing Up Against Static Electricity

STEM Activity

1

2

3

4

5

10 reviews

Have you ever wondered why rubbing a balloon or a blanket—or even a winter hat—on your head makes your hair stand up? The effect is due to static electricity, but how is the static electricity made, and why does it make your hair stand on end? Static electricity is the buildup of electrical charge in an object. Sometimes static electricity can suddenly discharge, such as when a bolt of lightning flashes through the sky. Other times, static electricity can cause objects to cling… Read more

Satellite Collision Detection: A Hands-On Coding Experience

Science Fair Project Idea

Engineering Design Process

Have you ever wondered what would happen if two satellites crashed into each other in space? While space may seem empty, Earth’s orbit is actually crowded with satellites and debris. In this project, you’ll step into the role of a space engineer, using real satellite data to model orbits, track their movement, and predict potential collisions. You’ll explore how gravity and speed affect a satellite’s movement and learn how scientists use simple math and code to prevent… Read more

Save Those Spoiling Strawberries!

Science Fair Project Idea

Scientific Method

Fresh strawberries and summer just go together. Walking through the local farmers' market on a warm day, the bright, red strawberries call out to you, beckoning you to buy them and take them home. The next day, as you get ready to savor the delicious berries, you notice that yesterday's juicy, red strawberries are now covered in...eewwww, mold! In this cooking and food science fair project, you will investigate thermotherapy and whether this technique can preserve strawberries and prevent mold… Read more

See Air Currents with Shadowgraphs and Schlieren Images

Science Fair Project Idea

Engineering Design Process

Have you ever wondered what the air currents look like around a candle? What about cold air flowing around an ice cube, or warm air rising from your hand? What about when you sneeze? We are surrounded by air currents all the time, but these subtle movements are completely invisible to the human eye. In this science project, you will take advantage of small changes in air density to make air currents visible in regular photographs and videos, using techniques called shadowgraphy and schlieren… Read more

Ninth Grade Science Experiments (top 2,000 results)

Explore Our Science Videos