Seventh Grade Science Projects (Page 72)

Polymer Permeability: Which Plastic Wrap Prevents Oxidation Best?

Science Fair Project Idea

Scientific Method

There are currently two different kinds of polymers used for kitchen plastic wrap: low density polyethylene (LDPE) (e.g. Saran or Glad Wrap) and polyvinyl chloride (PVC) (e.g. Reynolds PVC Foodservice Wrap or Boardwalk PVC Food Wrap Film). Which of these materials is less permeable to oxygen? When you slice an apple, the surface of the slice turns brown as the apple is oxidized. Can plastic wrap seal out oxygen and prevent the apple from browning? Which plastic wrap works best? Do… Read more

Do Different Tree Species Grow at the Same Rate?

Science Fair Project Idea

Scientific Method

Trees grow more during the early spring than they do the rest of the year. Because of this period of dormancy, or lack of growth, each year of growth is marked by a line called a tree ring. You can count the number of rings in the cross section of a tree trunk to show how old the tree is. You can also count the number of rings in a stem to see the age of a stem or branch. One way to measure the rate of growth of a tree is to count the number of rings per inch. Trees with high numbers of… Read more

The Effect of Roasting on Color, Flavor, and Texture of Peanut Butter

Science Fair Project Idea

Scientific Method

Peanut butter is a popular ingredient in sandwiches, cookies, and many other common foods. In this cooking and food science fair project, you will roast peanuts in the oven at 350 degrees for 20, 30, and 40 minutes to produce variable levels of color and flavor. Roasting not only adds complex flavors to the peanuts, but it also destroys enzymes that produce off-flavors. Each lot of roasted peanuts will be used to make a batch of peanut butter. You will evaluate each batch of peanut butter for… Read more

Strength of Different Construction Materials

Science Fair Project Idea

Scientific Method

There are many types of construction materials used for wood-frame houses. Compare the different uses for and strengths of different building materials, e.g.: particle board, plywood, pine, oriented strand board (OSB), and drywall (gypsum board, SheetRock). The Science Buddies Materials Science Resource Stress, Strength and Strain will be helpful for learning about different ways to measure material strength. You should be sure to use the same cross-sectional area of each material in order… Read more

How Quickly Does a Tennis Ball Lose Its Bounce?

Science Fair Project Idea

Scientific Method

The rebound rating is the ratio of the height the ball bounces to, divided by the height the ball was dropped from. Use the rebound rating to measure the bounciness of new tennis balls vs. balls that have been used for 10, 20, 50, and 100 games. Another idea to explore: does it matter what type of court the ball is used on? (See: Goodstein, 1999, 63-64.) Read more

Can Mulch Reduce Garden Water Requirements?

Science Fair Project Idea

Scientific Method

Divide a part of your garden into two equal plots, with each plot receiving equal amounts of sun. Cover one plot with two inches of organic mulch, such as compost or ground bark. Leave the other plot uncovered. Use the same amount of water for each plot for two or three weeks. At the beginning of the experiment, and at one-week intervals, dig down and check the soil in each plot for moisture content. Which plot holds water better? Which plot shows better plant growth? (McCausland, 2006) Read more

Are Soil Microorganisms Important for Plant Health?

Science Fair Project Idea

Scientific Method

Soil may look like a bunch of dirt, but good quality soil is actually a complex mixture of dirt, nutrients, microorganisms, insects and worms. What type of benefit do these microorganisms offer a growing plant? You can test this by baking soil in the oven to sterilize and kill the microorganisms. Do plants grown in sterile soil do better than plants in unsterilized soil? What about adding worms to one plant, but not to the other. Will the plant with worms grow better? Some insects are bad… Read more

Barometric Pressure and Weather

Science Fair Project Idea

Scientific Method

How does temperature change as barometric pressure changes? You can make a device to test this using a barometer and a thermometer on your stovetop. You can collect your own weather data from a barometer and thermometer over a period of a week or month. You can also use data from a weather station to plot the relationship between barometric pressure and temperature. Does the pressure change as humidity changes? Measure the pressure in a humid and non-humid environment (like your bathroom… Read more

Fungi Spores

Science Fair Project Idea

Scientific Method

Mushrooms are not plants, but are fungi. Fungi include mushrooms, molds, and lichen. They do not produce seeds to reproduce like some plants. Fungi produce spores, like more primitive plants do. The spores of a mushroom are contained in the tiny folds around the stem underneath the mushroom cap. Different species of mushrooms have different types of spores, with different colors and different patterns of folds. You can make mushroom prints by removing the stem from a mushroom and placing the… Read more

Physics of Vibrations

Science Fair Project Idea

Scientific Method

Tennis racquets, baseball bats and golf clubs all vibrate when they hit the ball. You can often feel it in your hands, particularly if you "mis-hit" the ball. You can find the point(s) on your racquet, bat or club—called the "sweet spot"—that minimize unwanted vibrations. Low-tech method: hang the racquet or bat straight up and down with a string from its handle. Lightly hold the handle with your thumb and forefinger and have a helper sharply tap the bat, strings or club face… Read more

Seventh Grade Science Projects (754 results)

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