Carol P. Boynton
Teachers in primary grades sometimes feel challenged when it comes to teaching science. Because most are not trained scientists, there can be a bit of intimidation for the less scientifically comfortable teachers. My initial intent is to design a unit that helps with that reticent feeling. Most adults have developed some kitchen skills and can appreciate the ability to create something edible. We also know that it is often through trial and error that we achieve a desired result, generally something that tastes and looks good! This is where the scientific method connects to day to day life - understanding that experiments may not be successful the first, second, or third time but learning that making adjustments based on results is truly the goal. This curriculum unit is designed to reach some developing scientists through a very common experience - eating the food we prepare! The focus will be learning and practicing the scientific method, a strategy that young students will need for their future science classes and experiences. Our annual science fair is a requirement for each classroom, thus participation requires learning about and executing the scientific method in every grade, kindergarten through eighth grade. The goal of this unit is to provide a set of experiences that will introduce a basic understanding of this method at work.
The instruction will begin with some introductory lessons on the basic units of measure and some hands-on experiences using tools for cooking. The unit then moves into learning the steps of the scientific method and carrying out these steps with lessons in measuring, mixing, and cooking, or more generally, physics and chemistry. Throughout the unit, data will be collected to create individual science journals detailing experiences just as scientists in a lab would do.
Science should be fun and interesting and should present experiences that get students thinking critically. Using the scientific method is a fundamental way for this to happen. By performing science experiments and analyzing the data, students are learning to become creative thinkers. Through the steps of the scientific method, students will learn how to define a problem, observe situations, take notes, synthesize the results, and come to a logical conclusion based on objective results. Certainly much of the time will be spent on direct instruction to explain and model the different parts of the scientific method. It will take some practice and experience for the students to get used to the science "discussion" and to learn how each of the parts of the method works. Using and understanding this process will help the students become more curious learners as well as analytical thinkers, a skill needed for all subjects.
Scientific Method
So why does the scientific method seem so mysterious? One possible reason could be the name itself. The word "method" implies that it is something rather secret or sacred only available to highly trained scientists and no one else. Of course, this is not the case. The scientific method is something all of us use. In fact, engaging in the basic activities that make up the scientific method - being curious, asking questions, seeking answers - is a natural part of being human. The scientific method is a systematic process of empirical investigation.
It is important to define what we are talking about. First of all science is an academic journey based on observation. Scientists use all of their senses to gather information about the world around them. Sometimes they gather this information directly, with no intervening tool or apparatus or at other times equipment may be used. Either way, scientists will write down what they see, hear and feel. These recorded observations are called data. Making observations and collecting data are not the ultimate goals rather what are needed to understand the world around us. Analyzing results requires inductive reasoning, or the ability to make generalizations based on specific observations. Also, science makes predictions and tests those predictions using experiments. Generalizations are powerful tools because they enable scientists to make predictions. And science is systematic, requiring tests to be repeated so that results can be verified.
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So, science can be thought of as a way of thinking, but also as a way of working -- a process requiring scientists to ask questions, make hypotheses and test their hypotheses through experimentation. This process is the scientific method, and its basic principles are used in every discipline, in every part of the world. Think about chemists developing new medicines, engineers designing new materials, ecologists working on waste management ideas. They are all armed with knowledge from science that has already been established and it allows them to build on that base. This process allows the world to progress, evolve and grow with today's advancements based on the achievements of scientists who have already done great work. One simple example: we know water (H
2
O) is made up of one oxygen (O) and two hydrogen atoms (H). Because many scientists have confirmed this fact through repeated tests, it is now considered a building block of knowledge, useful as a base for new experimentation.
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The scientific method actually has its roots in philosophy, as does science itself. Some names that we are aware of from history include Aristotle and Galileo who each played a part over time, in the development of this process. Of the many great thinkers and scientists, it is Aristotle who is credited with the beginning of modern scientific thought. He introduced syllogism, which means thinking from the general to the specific to draw a conclusion for example humans are mortal, I am human, therefore, I am mortal. Using observations and collecting data to learn about the world phenomena was the beginning of science. This was, of course, over 2000 years ago when Aristotle's search for knowledge and love of wisdom inspired people to think and learn about the idea of universal truths. Many centuries later, in the 1500's Galileo began to set up experiments to actually test these truths, one in particular being that heavy objects fall faster than light ones. Galileo rolled marbles down a ramp, and dropped various weighted cannon balls from the Tower of Pisa. Galileo experiments proved that objects will fall at the same speed regardless of weight in the absence of air pressure. So we now have observing, wondering, testing, and concluding. Throughout the 19
th
and 20
th
many scientists used the method and formed it into a consistent and accepted way to prove ideas through repeatable experiments.
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To specify and clarify each component or stage, these are the backbone steps or stages of the scientific method. And even though the scientific method is a series of steps, remember that new information or thinking might require you to back up and repeat steps at any point during the process.
Step One - Explore and Observe
Almost all scientific inquiry begins with an observation that piques curiosity or raises a question. This inquiry begins the same for scientists as it does for students - by exploring. By the time children start school, they have developed a variety of interests and understandings about things and happenings in their world. As children are innately curious, they are exposed to a range of phenomena in around them as they observe and explore. Using this excitement about the world gives teachers an opportunity to guide students through the process of obtaining answers to what interests them.
Step Two - Ask a Question
Coming up with scientific questions isn't difficult and doesn't require training as a scientist. Being curious about something or wanting to know what caused something to happen is already the beginning of a question that could generate a scientific investigation. Its helpful to guide students to start with a standard question word: what, when, why, who, where, and which.
Step Three - Make a Prediction / Guess
What could the answer to the question be? The great thing about a question is that it seems to ask for an answer, so the next step in the scientific method is to suggest a possible answer in the form of a hypothesis. A hypothesis is basically an educated guess or a working assumption because it is generally informed by what is already known about a topic. So the hypothesis is stated in a way that can be easily measured and of course in a way that will help you answer your original question.
Step Four - Design and Do the Experiment
Testing it out / Conducting the experiment - This is the step-by-step process needed to test the hypothesis. Often an experiment is thought of as something that takes place in a lab. While this can be true, experiments don't have to involve laboratory workbenches, Bunsen burners or test tubes. They do, however, have to be set up to test a specific hypothesis and they must be controlled. Controlling an experiment means controlling all of the variables so that only a single variable is studied. The independent variable is the one that's controlled and manipulated by the experimenter, whereas the dependent variable is not. As the independent variable is manipulated, the dependent variable is measured for variation. It is important that the test is designed to determine if the predictions were correct but it is also important that others are able to repeat the experiment to verify results.
Step Five - Analyzing the Results / Drawing Conclusions
After collecting the data you need to determine what it tells you about your hypothesis. The ultimate goal is to improve the hypothesis and, in doing so, define further experiments which will allow you to answer the original question.
These steps are organized to get scientists, even young ones, through the process but also understanding, as in the diagram below that this is in fact a cycle that can and should be repeated and retried from any and all steps.
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This is not unlike the adage, if at first you don't succeed, try, try again. And it should be stressed that the success is in doing to experiment and learning new information from it and not necessarily in getting the answer you think it should be.