Experiments I. (Grade 6)
|CCSTD Science Grade 6 7.a.|
Why do leaves change color in autumn? Why do earthworms crawl up on sidewalks after it rains? Scientists ask questions like these every day. They may need to take different methods to find answers to different questions. A while ago, scientists discovered that leaves change color because their chlorophyll breaks down. These scientists used different methods than those who found out that earthworms crawl out of soil to keep from drowning (http://phyun5.ucr.edu/~wudka/Physics7/Notes_www/node6.html).
Even though scientists may use different approaches to answer different questions, all share some techniques in common. These common steps are called the scientific method (http://www.biology4kids.com/files/studies_scimethod.html)
Are you a curious person? Do your friends think that you are observant? Curiosity is often the beginning of discovery in science. Sometimes the answer to one question will also help clear up other questions. Every so often, scientists make accidental discoveries along the way. They may discover that a certain element kills cancer cells, or that a certain plantís leaves can be used as a medicine. On the other hand, sometimes the answer to one question leads to more questions. Science is one big adventure in discovery.
The first step in discovery is to ask a question. Perhaps you have noticed windmills spinning at wind power plants, and you want to know how wind could be used to power things.
After you ask the question, you take your best guess as to the questionís answer. You will need to test your answer to find out if you are right. If you canít test your answer, you canít prove that you are right. A hypothesis is a testable answer to a question or problem.
A hypothesis is not just a random guess, it is the best guess you can make. Before you make a hypothesis, you must do some background work. This may include personal observation, reading and researching, or experiments that you do beforehand.
After you state your hypothesis, you may continue your observation and research. Doing this may cause you to form additional hypotheses. There may be other answers to your question that seem just as reasonable as your first one.
Later, you will probably test your hypothesis by conducting an experiment. The results of your experiment will help you decide whether your hypothesis was correct or not.