Understanding and Using The Scientific Method

Transcription

1 The Scientific Method by Science Made Simple Made Simple Understanding and Using The Scientific Method Now that you have a pretty good idea of the question you want to ask, it's time to use the Scientific Method to design an experiment which will be able to answer that question. If your experiment isn't designed well, you may not get the correct answer, or may not even get any definitive answer at all. In this section we will take a look at the method you should use to design your research. This method is the most important part of science--in fact, it's called the "Scientific Method." The Scientific Method is a way to make sure that your experiment can give a good answer to your specific question. Steps of the Scientific Method Observation/Research Hypothesis Prediction Experimentation Conclusion The Scientific Method is a logical and rational order of steps by which scientists come to conclusions about the world around them. The Scientific Method helps to organize thoughts and procedures so that scientists can be confident in the answers they find. Scientists use observations, hypotheses, and deductions to make these conclusions, just like you will use the Scientific Method in your science fair project. You will think through the various possibilities using the Scientific Method to eventually come to an answer to your original question. The observation is done first so that you know how you want to go about your research. The hypothesis is the answer you think you'll find. The prediction is your specific belief about the scientific idea: If my hypothesis is true, then I predict we will discover... The experiment is the tool that you invent to answer the question, and the conclusion is the answer that the experiment gives. Don't worry, it isn't that complicated. Let's look at each one of these points individually so that you can understand the tools that scientists use when doing their own science projects and use them for your project. OBSERVATION This step could also be called "research." It is the first stage in understanding the problem you have chosen. After you decide on your area of science and the specific question you want to ask, you will need to research everything that you can find about the problem. You can collect information on your science fair topic from your own experiences, books, the internet, or even smaller "unofficial" experiments. This initial research should play a big part in the science fair idea that you finally choose. Let's take the example of the tomatoes in the garden. You like to garden, and notice that some tomatoes are bigger than others and wonder why. Because of this personal experience and an interest in the problem, you decide to learn more about what makes plants grow. For this stage of the Scientific Method, it's important to use as many sources as you can find. The more information you have on your science fair project topic, the better the design of your experiment is going to be, and the better your science fair project is going to be overall. Also try to get information from your teachers or librarians, or professionals who know something about your science fair topic. They can help to guide you to a solid experimental setup. HYPOTHESIS The next stage of the Scientific Method is known as the "hypothesis." This word basically means "a possible solution to a problem, based on knowledge and research." The hypothesis is a simple statement that defines what you think the outcome of your experiment will be. All of the first stage of the Scientific Method -- the observation, or research stage -- is designed to help you express a problem in a single question ("Does the amount of sunlight in a garden affect tomato size?") and propose an answer to the question based on what you know. The experiment that you will design is done to test the hypothesis. Using the example of the tomato experiment, here is an example of a hypothesis: TOPIC: "Does the amount of sunlight a tomato plant receives affect the size of the tomatoes?" HYPOTHESIS: "I believe that the more sunlight a tomato plant receives, the larger the tomatoes will grow. This hypothesis is based on: (1) Tomato plants need sunshine to make food through photosynthesis, and logically, more sun means more food, and; (2) Through informal, exploratory observations of plants in a garden, those with more sunlight appear to grow bigger. PREDICTION The hypothesis is your general statement of how you think the scientific phenomenon in question works. Your prediction lets you get specific -- how will you demonstrate that your hypothesis is true? The experiment that you will design is done to test the prediction. An important thing to remember during this stage of the scientific method is that once you develop a hypothesis and a prediction, you shouldn't change it, even if the results of your experiment show that you were wrong. An incorrect prediction does NOT mean that you "failed." It just means that the experiment brought some new facts to light that maybe you hadn't thought about before. The judges at your science fair will not take points off simply because your results don't match up with your hypothesis. Continuing our tomato plant example, a good prediction would be: Increasing the amount of sunlight tomato plants in my experiment receive will cause an increase in their size compared to identical plants that received the same care but less light.

2 EXPERIMENT This is the part of the scientific method that tests your hypothesis. An experiment is a tool that you design to find out if your ideas about your topic are right or wrong. It is absolutely necessary to design a science fair experiment that will accurately test your hypothesis. The experiment is the most important part of the scientific method. It's the logical process that lets scientists learn about the world. On the next page, we'll discuss the ways that you can go about designing a science fair experiment idea. CONCLUSION he final step in the scientific method is the conclusion. This is a summary of the experiment's results, and how those results match up to your hypothesis. You have two options for your conclusions: based on your results, either (1) you CAN REJECT the hypothesis, or (2) you CAN NOT REJECT the hypothesis. This is an important point. You can not PROVE the hypothesis with a single experiment, because there is a chance that you made an error somewhere along the way. What you can say is that your results SUPPORT the original hypothesis. If your original hypothesis didn't match up with the final results of your experiment, don't change the hypothesis. Instead, try to explain what might have been wrong with your original hypothesis. What information did you not have originally that caused you to be wrong in your prediction? What are the reasons that the hypothesis and experimental results didn't match up? Remember, a science fair experiment isn't a failure if it proves your hypothesis wrong or if your prediction isn't accurate. No one will take points off for that. A science fair experiment is only a failure if its design is flawed. A flawed experiment is one that (1) doesn't keep its variables under control, and (2) doesn't sufficiently answer the question that you asked of it. Design your science fair experiment to get the best results Now that you have a pretty good idea of the question you want to ask, it's time to use the Scientific Method to design an experiment which will be able to answer that question. If your experiment isn't designed well, you may not get the correct answer, or may not even get any definitive answer at all. An experiment is made up of two nearly identical parts--let's say, two trays of tomato plants. The tiny differences that will test your hypothesis are called "variables." Let's look at the three kinds of variables. The Independent Variable: This is a variable that you intentionally change. In the case of our tomato plant experiment, it would be the brightness of the light in Tray #1. The Dependent Variable: This is the difference between the two parts of the experiment that happens when the independent variable is changed. In this case, it would be the size of the tomatoes in Tray #1. So you turn the up the lights in Tray #1 (the independent variable) and the tomatoes get bigger (dependent variable). The Controlled Variables: These are the variables that are kept the same in Tray #2. In other words, when you turn the lights up in Tray #1, the lights in Tray #2 stay the same. So when the tomatoes in Tray #1 get bigger, you can say that the difference in size between the tomatoes in Tray #1 and Tray #2 is the result of the independent variable, or the light that you made brighter. Tray #2 is called a "control group." This is an identical setup to Tray #1, but it is kept in its natural, unchanged state. Tray #1 is called the "experimental group." So when you change something in the experimental group (like the brightness of the light), the control group stays the same so that you can measure changes in you dependent variable (the size of the tomatoes). Important Design Tips When you design your science fair experiment, you have to keep as many things identical as possible. For instance, the lights that you use to grow the tomato plants have to use the same light bulbs. The trays have to be the same, just like the soil has to be the same. The amount of water has to be the same too. You should think very hard about differences that might try to sneak by you. For instance, when planting the tomato seeds, did they come from the same package? They should if you want to keep things under control. The only thing that can be different between the two identical groups is the thing that you are testing - in this case, light. The exact nature of your variables will depend on your exact science fair experiment idea. If you changed the amount of light, AND changed the amount of water each plant received, you wouldn't know if the bigger tomatoes were because of the light, or the water! So it's absolutely critical to have everything be as close to identical or "controlled" as you can get it. Once you've done your science fair experiment, consider repeating it if you have the time! This is very impressive for science fair judges, and really helps to make your results convincing.

3 If you conduct your experiment and the results just don't seem right, you might consider reviewing your experiment idea, and possibly even modifying your experimental design so that your science fair experiment will produce accurate results. Presenting Your Science Project Results This is it - the big day is finally here! Everyone will be looking at your science fair display board, reading your science fair report, and listening to your presentation, which must all present your project in the best possible way. All of your work must be summarized here. This is your chance to show the world everything you've learned from your experiment. Your science fair display and report are the ways that the science fair judges will remember your project when they make their decision. It's important that your scientific work was good, but that's not everything... Science Fair Display Boards So how should you set up your science fair display? Let's look at the basics. A science fair display should consist of a back board, sometimes sold specifically as a science fair display board, a project report, graphs and charts, and some representation of your experiment. Of course it would be great if you could also bring your science fair experiment into the fair, but if it's too big, or if it was strictly observational, consider bringing in photographs or a part of the experimental apparatus. Some people even bring in a small television and show a video presentation of their science fair experiment. Whatever methods you choose, your science fair display has to represent your project in such a way that it holds the interest of the judges--so be creative, but keep it simple. The size and shape of science fair display boards can vary, so be sure to check the rules for your particular science fair. Some maximum sizes for most science fairs are 48 inches wide, 30 inches deep, and 108 inches from the floor. Generally speaking, no matter the size, a traditional science fair board is divided into three sections: the main center section, and two "wings" which are folded toward the front. These science fair boards can be made from scratch from heavy cardboard or wood, or can be ordered inexpensively over the internet. Now, think about the things you'll want to attach to the science fair display board. Some science fairs, and most teachers, have rules or guidelines for what should be attached to the science fair board. These might include cut-out lines of text which detail your original question (which will be your project topic), your hypothesis, results, conclusions, and other information including charts and graphs. The title of your project should always go on the center panel at the top of your science fair display board. It must be large enough so that people can see it from about three feet away. The other pieces of text can be smaller, and should be placed in a logical order. In other words, let the judges read your hypothesis before they read your conclusions. Several years ago, it was common to use stenciled or cut-out letters mounted on the science fair display board, but now that most students have access to computer word processors and printers, it is more common for these lines of text to be printed in large letters. There is no rule about this, but be aware that looks do matter at the science fair. A word printed on a laser printer looks a lot better than one drawn and colored with a marker. It's very important that you present a science fair display board that the judges will remember in a good way, and not just because it used bright colors and big letters. You want the science fair board to look professional and well-organized so that the judges aren't distracted. Make it look professional, and the judges will treat your project professionally. Science Fair Report & Presentation Whether your teacher requires an in-class science fair report and presentation of your science project, or it's just for the judges at the fair, you will probably have to give an oral presentation on the content of your science project. There may or may not be a time limit, but even if there isn't, it's important to keep your presentation short and to-the-point. Be sure that your science fair report touches on all of the elements of your project, including but not limited to the points of the Scientific Method. Be sure to practice, preferably in front of an audience. Giving an oral presentation and talking to the judges, who may be teachers or professionals you've never met before, could end up being the hardest part of the science project. Practice will give you the confidence you need to sound like an authority in your area of research, and that's something that the judges like to hear. Points at a science fair are awarded for your ability to discuss the project clearly, explaining each stage of your research and every step of your experiment. The judges will ask you questions, and so practice will really help. Have someone you know ask you questions about your project. It might make you think about things that you haven't thought of before. Important Tips NEVER make up answers to difficult questions. Instead of admitting that you don't know, tell the judges that you didn't discover the answer to that question during your research, and then present other, relevant information. Finally, your appearance may also affect the way that the judges view you. A professional appearance will reflect well on you and your project. You are not only trying to look professional yourself, but you are trying to make your project look like the result of thoughtful, mature, and professional scientific research. /In summary, it's important that you have a professional-looking, well-organized science fair display board to make a good impression on the judges. It is also important that you appear relaxed and knowledgable while presenting your science fair report.

4 Winning science fair projects - What are judges looking for? To produce an award-winning science fair project, you need to understand how the judges select a science fair winner. The point scoring system for your science fair may differ from others -- there is no standardized point system -- but generally speaking, science fair judges use similar methods of judging. Usually, they start with a neutral score, not good or bad, and then add or subtract points, depending on the performance of the presenter, to reach a final score. The following list of tips should help you improve your score. OBJECTIVES Is your project full of original and well-thought-out ideas? Were you clear in describing the problem you were researching? Be sure you know your material, especially the content of your final report. Was your science fair project too easy? A difficult or advanced project can make a difference in how the judges evaluate it, and whether or not it becomes a winning science fair project. SKILLS Are you knowledgeable about the experiment itself--did you design it and perform the experiments? Having a good command of the technical aspects of your project reflects very well on you. Know what you're talking about, and know your experimental data, but also know the ins and outs of the experimental apparatus. DATA Was your data collection scientific and professional? Be sure to use a journal to record data from the experiment. This demonstrates organization. Did you repeat the experiment? Repetition lends much more reliability to your data. Repeat it if you have time. INTERPRETATION Is your use of tables and graphs helpful to the judges in understanding your data? Did you use the tables and graphs correctly and collect enough data to reach a reliable conclusion? Make sure that you are confident in your final numbers. Science is all about proof. FINAL PRESENTATION Are you able to answer the judges' questions knowledgeably and confidently? Be sure to use your display while the judges talk to you. It isn't just a backdrop, it's a visual aid to the information that you've worked so hard to obtain. Make sure that you explain every element of the board and make sure that the board looks as professional as possible. ONE LAST TIP The final judging is mostly subjective. While the judges are looking for a few specific things, the way that you represent yourself and your project, and the way that your display board looks can make the difference between leaving a poor impression, and impressing the judges with your award winning science fair project. Science Fair Projects - 5 Valuable Benefits For Your Child Science fair projects can be really exciting, especially now with all the opportunities the internet gives us. Most kids know how to use a computer for fun and spend many hours a week surfing the net. As parents, we would like to encourage them to use some of their computer time for schoolwork and educational projects. And researching scientific ideas and the scientific method is certainly a good use of their time. But in addition, there are many other great reasons for encouraging your children to do science fair projects.

5 (1) A science fair project is an activity that integrates almost every skill children have been taught. Students must learn how to apply their existing abilities to new areas, as well as learn many new skills. A science fair project can involve reading, logical thinking, writing, grammar and spelling, math, statistics and data analysis, computer science, and graphic arts, as well as scientific methodology. If a student participates in a formal competition, then they will also practice public speaking, and learn how to explain and defend their work in front of a panel of judges. (2) Participating in science fair projects helps develop a feeling of confidence and competence among students, and fosters a spirit of scientific inquiry. Projects usually involve scientific questions that the student is interested in, and a specific topic they have chosen for themselves. Participants must research their question, learn and apply the scientific method to create a valid experiment, and think about the meaning of their results. Some kids get so immersed in their project that they forget about other factors like prizes or the fact that they are actually learning new skills. Science fairs are also a way for students to demonstrate motivation, self-learning, critical thinking, ethics and other important skills and traits. (3) A science fair project is an experience that can be challenging and self-validating. Many students actually do important research and discover previously unknown facts. (4) Many science fairs offer cash prizes, which can be a significant incentive for some people. They also help open the doors of academic opportunity for students. Winners at regional fairs receive recognition for their work, and gain the right to participate at state-level and higher-level competitions. (5) Some of those kids (maybe yours someday) qualify for the international competition at the annual Intel International Science and Engineering Fair. Here the level of cash prizes is significant. In addition, those whose projects qualify for international competitions are judged by the best in the world: top scientists and people from industry. Imagine your child having his or her project judged by a Nobel Laureate. These kinds of things do immeasurable good for the confidence of the student and certainly encourage them further in all of their activities.