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Fourth Grade, Plant Biology Science Projects (17 results)

Plants provide us with so much — oxygen to breath, food to eat, materials to make clothing and paper, and beautiful flowers and leaves to admire! How can plants be so diverse and survive in so many kinds of climates? How do they know how to grow towards the sun? Why do some plants not have seeds? Explore the amazing and beautiful world of plants.

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Science Fair Project Idea
What do plants need to grow? Most of us would answer that they need light, air, water, and soil. But by using a process called hydroponics, you can grow plants without soil! How does it work? Try this project and see for yourself! Read more
Science Fair Project Idea
Plants need nitrogen to grow healthy stems and leaves. Although nitrogen is the most abundant element in the air we breathe, that form of nitrogen cannot be used by plants. Nitrogen contained in fertilizer, on the other hand, is readily taken up by plants. In this experiment, you will compare plants grown without nitrogen fertilizer to plants grown with nitrogen fertilizer. Read more
Science Fair Project Idea
To be able to live on Mars, humans need breathable air, clean water, and nutritious food. Spacesuits can provide oxygen to breathe, ice on Mars can be a source of water, but how could we get nutritious food? Today's astronauts bring food with them. But a manned trip to Mars would require food that was either successfully grown in space or on Mars, as taking the extra weight of food for such a long time—it takes 6–9 months one way—is just too costly. In this project, you will… Read more
Science Fair Project Idea
You might not know it, but plants are able to sense their environment and actually respond appropriately. One of the key parameters that every plant must respond to is the direction of gravity: stems go up (opposite to the pull of gravity) and roots go down (in the same direction as the force of gravity). In this project, you will construct simple devices that hold several germinating seeds, which allow you to watch how growing rootlets respond as you rotate the devices, effectively altering… Read more
Science Fair Project Idea
Up, up, and away! If you have ever made a wish and blown the fluff of a dandelion, you have witnessed how some plants are adapted to spreading their seeds using the wind. The tiny, furry parachute allows the seeds to be picked up by the wind and to be carried far away from their parent plant. In this experiment, you will make models of seeds and fruit to investigate dispersal by wind and to evaluate the relationship between the structure of the seed and its ability to be dispersed by the… Read more
Science Fair Project Idea
Some plants grow only in water-logged environments. These plants are usually native to wetlands and are important for the sustainability of aquatic ecosystems. Wetland ecosystems are very fragile and susceptible to the toxic dumping of sewage and fertilizer run-off from neighboring farm land. One very common aquatic plant called duckweed inhabits many wetland marshes. Duckweed grows by asexual reproduction and floats at the surface of the water with tiny roots extending into the water below.… Read more
Science Fair Project Idea
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
Science Fair Project Idea
Global warming is how scientists describe the gradual warming of our global climate. Scientists think that the trend towards global warming can be attributed to the build up of greenhouse gases in the earth's atmosphere from industrialization. Another problem is deforestation, as we remove plants and trees from the environment to meet a high demand for lumber or by clear cutting fields for farming and urbanization. By removing trees from the earth's environment, are we changing how greenhouse… Read more
Science Fair Project Idea
Like humans, plants can be negatively affected by overcrowding. Unlike humans, plants cannot get up and move to a new environment or explore how to utilize new resources. This experiment will explore the effects of crowding (population density) on the growth and health of plants. Read more
Science Fair Project Idea
Have you ever gone camping, looked up at the stars, and found the Big Dipper? Two stars in the dipper part of this constellation point to Polaris, the north star, which people have used for thousands of years to help them find their way. In this plant biology science fair project, you'll investigate whether plants, like moss, can help you find your way, too. Read more
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