The biological study of plants and plant science is called botany. Many botany science projects and experiments focus on the way that plants grow. For instance, students can grow two plants, one that is receiving just water and sunlight and the other that receives a caffeine supplement in the soil. Students then observe the effect of caffeine on plant growth. Another experiment compares the effect of earthworms in soil. Similar to the caffeine experiment, two plants are grown -- one with earthworms and one without. Students observe the germination and growth of both plants to see if the earthworms affect plant growth.
Biology projects and experience in the field of human anatomy explore the bodily systems and physiology of humans. One such experiment, good for elementary school students, tests the effect of cold water on a person's voice. Five students sing ascending notes until they reach the highest note they can sing. Then they drink water of different temperatures and repeat the singing process to see if they can hit the same high note. Another more advanced project tests the sense of smell to see if it can determine the difference between natural and synthetic scents. Students smell tissues that have each been dipped in a natural or synthetic scent and must identify the natural one.
Zoology is the study of animals and their biological functions, evolution and cell structures. One example of a zoology science experiment is testing the ability of turtles to identify color. For a week before the experiment is conducted, students train a turtle to eat from a blue food dish. Once the turtles have been trained, they are fed from three different food dishes of different colors: blue, red and yellow. The turtles are observed for two days to see which food dish they prefer. This experiment helps students understand the structure of a turtle's eye, as well as their ability to be trained.
Microbiology is the study microscopic living organisms, such as bacteria, fungus, viruses and yeast. Once bacterial biology project involves observing the growth of mold on bread given different conditions: in a moist, dark place, direct sunlight, an airtight bag and a refrigerator. Students observe the bread daily with a magnifying glass and compare how the bread appears. This helps students learn about what conditions are required for bacteria to thrive.