Third Grade Science Projects (Page 30)

Attractants and Repellants

Science Fair Project Idea

Scientific Method

Animals respond to chemical cues in different ways. If an animal turns away from a chemical cue, then that chemical is a repellent. If an animal turns toward a chemical cue, then that chemical is an attractant. Attractants and repellents can be airborne chemicals, chemicals found in food, or chemicals that diffuse through water. One example of an airborne chemical is a pheromone, a chemical signal that is released by one individual to attract another. Moths release pheromones to attract… Read more

Are Enzymes in Laundry Detergents Effective Stain Removers?

Science Fair Project Idea

Scientific Method

Some laundry detergents have added enzymes that break down proteins, helping to remove them from the cloth fibers, and thus remove stains. You can perform a scientific test of these enzymes' stain-fighting ability. Do background research on the enzyme(s) in the detergent, and on the substances you choose for making the stains. Try to predict for which substances the enzymes will be effective. Cut a piece of light-colored cotton cloth into identical 10 cm squares. Choose different… Read more

How Much Do Different Pet Species Eat Compared to Each Other?

Science Fair Project Idea

Scientific Method

Are you in charge of feeding your family pet? How much food do you think your pet eats compared to other kinds of pets? After adjusting for your pet's body weight, you might be surprised how it will compare to other kinds of pets. What type of pet do you think will eat the most for its body weight? Read more

Oil and Vinegar Do Mix…When You Have an Emulsifier

Science Fair Project Idea

Scientific Method

In this cooking and food science fair project, you will explore the role of proteins as emulsifying agents. Emulsifying agents are substances that are soluble in both fat and water and enable fat to be uniformly dispersed in water as an emulsion. Foods that consist of such emulsions include butter, margarine, salad dressings, mayonnaise, and ice cream. Emulsifying agents are also used in baking to aid the smooth incorporation of fat into the dough and to keep the baked goods tender. Natural… Read more

Use the Sun's Energy to Heat Your Own Water

Science Fair Project Idea

Scientific Method

Isn't it nice to take a nice, hot shower or bath after a long day of playing outside? But have you really thought about how the hot water in your shower or bath gets hot? Sure, the water heater in your house gets it hot, but what makes the water heater work? Water heaters are powered by natural gas or electricity. But are there any other ways to heat water? What about using the Sun? In this science fair project, you'll give it a try by capturing energy from the Sun to heat water. Read more

Separating Mixtures: Can You Design a Device to Do It?

Science Fair Project Idea

Scientific Method

Have you ever looked in the kitchen cupboard and found a container of tiny white grains, but you were not sure if they were sugar or salt? They look very similar. How could you tell them apart? Well, you know that sugar and salt taste very different. Taste is actually called a property, and properties are used to describe and identify different materials. Properties can also be used to physically separate things. In this science project, you will use different properties to create a way to… Read more

Spinning Colors: How Do Primary Colors Combine to Make New Colors?

Science Fair Project Idea

Scientific Method

Did you know that sunlight can actually be separated into the colors of the rainbow? And the light of different colors can be added together to make white light or new colors. This is an area of study where art and science overlap. In this science fair project, you will explore this area by drawing or painting "pie slices" onto a white circle and then combining them to make a new color by spinning the wheel using an electric drill. Read more

Is That Cat Overweight?

Science Fair Project Idea

Scientific Method

Did you know that there are millions of overweight cats and dogs in the United States? Is your pet one of them? How about your neighbor's cat or your grandma's dog? In this science project you'll determine what percentage of the pets you know are overweight and how their weights compare to pets' weights throughout the United States. Read more

Air Pollution

Science Fair Project Idea

Scientific Method

Smog days are often posted in your local newspaper. Check how many smog days your city has had in the last year. How does it compare to to other years? You can also take pictures of your city landscape on high and low smog days. How do the pictures compare? How does smog in the atmosphere affect visibility? What is smog made of? You can use tongue depressors smeared with Vaseline to check for smog particles in different areas; just stick in the ground and look at them a few days later. … Read more

Frequency of Outcomes in a Small Number of Trials

Science Fair Project Idea

Scientific Method

People often draw conclusions from a small number of observations, and use those conclusions to evaluate the likelihood that an event will take place. But how easy is it to draw the wrong conclusion based on those observations? Will your predictions be accurate if an experiment is only performed a few times? The objective of this project is to determine what happens when a test with two equally-likely outcomes is performed only a small number of times. You can test this by flipping a coin. A… Read more

Third Grade Science Projects (386 results)

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