Ninth Grade Projects, Lessons, Activities (Page 25)

Build a Sound-Tracking Search and Rescue Robot

Science Fair Project Idea

Engineering Design Process

HELP! Locating survivors trapped under rubble is a difficult and dangerous task. After a natural disaster, like an earthquake, rescuers must act quickly to save as many lives as possible. They can use robots with different types of sensors to help find survivors. In this project you will build a sound-tracking robot that can use two microphones to drive toward a sound source. Designing the robot's algorithm will be up to you. Read more

Crack the Code: Breaking a Caesar Cipher

Science Fair Project Idea

Scientific Method

When you hear the word "encryption," you might think about modern computers and things like email and online bank accounts. But did you know that encryption has been around for thousands of years? In this project you will learn about the Caesar cipher, a simple type of encryption that replaces each letter of the alphabet with another letter, and demonstrate how a modern computer can crack this ancient code in just a few seconds. Read more

Death Rays: What Duration of Ultraviolet Exposure Kills Bacteria?

Science Fair Project Idea

Scientific Method

Ultraviolet light can damage DNA molecules. If a cell's DNA repair mechanisms can't keep up with the damage, mutations are the result. As harmful mutations accumulate, the cell eventually dies. How much ultraviolet light is too much for a bacterial cell? Read more

Distance and Constant Acceleration

Science Fair Project Idea

Scientific Method

Have you ever dropped something and wondered how fast it was moving while falling? If it was something fragile, like a cell phone, you might not have been thinking about this at the time — you may have been too busy trying to grab the phone! But you probably wanted to find out just how hard it hit the ground afterwards. We know that gravity forces an object to fall, but how does this affect how quickly something falls and how hard it hits the ground? For example, did the phone move faster… Read more

Do Oranges Lose or Gain Vitamin C After Being Picked?

Science Fair Project Idea

Scientific Method

Are oranges highest in vitamin C when they are fresh from the tree (or, in a pinch, the grocery shelf)? Does the amount of vitamin C in an orange change over time, after it has been picked? In this science project, you will find answers to these questions by measuring the amount of vitamin C in a solution using an iodine titration method. Read more

Do Your Storm Drains Keep the Ocean Trash Free?

Science Fair Project Idea

Scientific Method

Did you know that there is plastic in the ocean? It probably isn't too hard to imagine that some of the plastic that litters roadways, sidewalks, and parks finds its way into the ocean. So, how much do you think is in there? Hundreds of pounds of plastic? How about thousands of pounds? No one knows for sure, but estimates, based on scientific surveys, suggest the amount is in the range of millions of pounds of plastic! Of course, the ocean is big, over 300 million square kilometers, so… Read more

Do-Re-Mi with Straws

STEM Activity

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Have you ever wondered how a musical instrument produces the beautiful sounds that it does? To make a certain note, the instrument has to make a certain sound wave. Depending on the instrument, the sound wave that is made can be affected by changing the length of part of the instrument, such as the strings in a piano or on a guitar, or a trombone’s air column. In this science activity, you will make your own musical instruments using drinking straws and explore how changing the length of the… Read more

Efficient LED Circuit Design

Science Fair Project Idea

Engineering Design Process

LED lighting can add a cool ambient effect to a room, a device, or even the inside of a car. You may know that LED lights are more efficient than incandescent bulbs, but do you know how to design and build your own LED circuit? How would you minimize power consumption and maximize efficiency? In this project you will learn how to design and build your own LED circuits so you can add LED lighting effects wherever you want. Check out this page for more LED science projects. Read more

Electric Paint: Light Up Your Painting

Science Fair Project Idea

Scientific Method

Electric paint is a fun way to include a circuit with lights in an art project, but it presents a challenge not found in traditional electronic circuits. What happens if you change the length or width of your strokes of paint, such as by painting longer, curvier lines or using a thicker brush? Could this affect the electrical properties of your circuit? Try this project to find out! Read more

Excess Volume: Investigate the "Shrinking Liquids" Effect

Science Fair Project Idea

Scientific Method

Cooking, washing, and many industrial processes involve the mixing of liquids. How liquids behave when they are mixed is dependent on many factors. Sometimes, the mixing behavior of liquids can be quite surprising! For example, when you mix 50 mL of one liquid with 50 mL of another liquid, you might not end up with a 100 mL mixture! In this science project, you will explore this phenomenon, which we call the "excess volume" of mixtures. How do you think your mixing volumes will… Read more

Ninth Grade Projects, Lessons, Activities (792 results)

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