Dirtmeister: Simple Machines Teacher's Guide

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			Dirtmeister's Science Reporters: Simple Machines Grade Levels: 3–6
	MENU Activity Snapshot National Standards Correlations How to Use this Activity Background Information Extensions Resources		Activity Snapshot Science is all around us — from a bicycle brake to a pine cone to a flag pole. In "Dirtmeister's Science Reporters," students lead their own investigation in observing, identifying, and describing the science found in their world — then write about their findings. With the help of science expert Steve Tomecek (the "Dirtmeister"), students learn to ask scientific questions, communicate their observations, and construct explanations of natural phenomena. This activity offers an exciting way to teach inquiry-based science, as each new investigation helps reinforce basic science concepts. Learning Objectives Through participation in "Dirtmeister's Science Reporters," students will: Explore, observe, and describe the world around them. Identify various phenomena in the real world. Investigate materials, organisms, and properties of common objects. Construct explanations of natural and man-made phenomena. Develop the ability to ask scientific questions, investigate aspects of the world around them, and use their observations to construct reasonable explanations for the questions posed. Ask questions about objects, organisms, and events in the environment. Use data to construct a reasonable explanation. Communicate their ideas to others. Develop their science knowledge. Learn through the inquiry process how to communicate their own investigations. Time Required Teachers who participate in "Dirtmeister's Science Reporters" should allow students two class periods (45-minute blocks) to complete the assignment. This includes time for students to retrieve and review the assignment, read the background material, find and observe their subject, answer questions about their findings, and write their reports. You may wish to assign the step of finding and observing a subject as homework. We also suggest that students who participate submit a "draft" of their report to you before final writing. In this way, you can determine if the student is "on target" with his or her assignment. Top of Page National Standards Correlations The "Dirtmeister's Science Reporters" simple machines investigation helps students meet the following science content standards as set forth by the National Research Council of the National Academy of Sciences. Students conduct a simple investigation. (Content Standard A) Students employ simple equipment and tools to gather data and extend the senses. (Content Standard A) Students use data to construct a reasonable explanation of how simple machines work. (Content Standard A) Students communicate investigations and explanations. (Content Standard A) Students discover that the position and motion of objects can be changed by pushing or pulling. The size of the change is related to the strength of the push or pull. (Content Standard B) Technological solutions have intended benefits and unintended consequences. Some consequences can be predicted, others cannot. (Content Standard E) Students learn that people continue inventing new ways of doing things, solving problems, and getting work done. (Content Standard F) Top of Page How to Use This Activity In "Dirtmeister's Science Reporters" students are introduced to new science concepts. After gaining knowledge about the concept by reading background information, students seek out an example of that concept in the real world — whether it's found in their home, school, or community. They answer questions about their observations using an observation sheet provided by the Dirtmeister. This observation sheet encourages scientific observation, critical thinking, and directed student writing. Finally, students write their reports. They can see samples of what other students have found. Top of Page Background Information: Simple Machines As students learn about simple machines, they are challenged to find, observe, and record one simple machine used around their home, school, or community. What is a simple machine? Well, the purpose of a machine, whether simple or complex, is to accomplish work more easily by somehow transforming energy or motion. To put it another way, machines help you get a job done with less effort. "Simple machines" are so named because they have few, if any, moving parts. Simple machines include the lever, the screw, the wheel and axle, the inclined plane, the pulley, and the wedge. (The Dirtmeister has provided basic information about each of these simple machines for students in Investigate the Facts) All simple machines appear to give you "free energy," because in using them your effort is reduced. The truth of the matter is that in using a simple machine, you actually do the same amount of work, it just seems easier. To understand this, we must look at the scientific definition of "work." Essentially, "work" only happens when you move an object over a certain distance. It may seem strange, but you accomplish more work lifting a pencil than trying to push against a wall, because if the wall doesn't move, no work is done! Since work is accomplished by having a certain amount of force acting over a distance, you can think of it as a simple mathematical formula: Work = Force x Distance. If you keep the amount of work the same and you decrease the amount of force, the distance must increase. This is exactly what happens with most simple machines! They reduce the effort (force) needed to get the job done. However, you're moving things a greater distance. In short, the equation balances out and in the end, the amount of work you do is exactly the same. As the Dirtmeister explains to the students, there's always a "trade-off" of effort with simple machines. In their reports, students are asked to describe this trade-off in the simple machines they observe. Top of Page Extensions Here are some suggestions to enhance the experience of Dirtmeister's Science Reporters for your students: Have the class make a list of all the simple machines that they encounter in the course of a week. What are some of the common tools and devices that use simple machines and where can they be found in different rooms of their home? Have the class research where simple machines have been used in the past to solve problems in engineering. Were any ancient structures built with the help of simple machines? Have students analyze complex machines or even their own bodies to see how many simple machines they can find. Your arm is really a lever and many joints and tendons work like pulleys! For advanced students, work out the mathematics of machines. Use the formula for work (Work = Force x Distance) and measurements of motion in some common machines like a lever or a ramp to prove that they don't really give you "free energy." Talk with your school librarian or media specialist about researching machines in the library, including books and multimedia resources. (See "Resources" section below.) Have the class use the computer to search the Web for supplementary articles on simple machines and their uses. Provide space on a classroom bulletin board for the Dirtmeister's Science Reporters. Using computer software such as ClarisWorks or Microsoft Works, have students create and maintain electronic science journals. Encourage students to illustrate their work by using drawing or painting features of the software. This is an excellent way of keeping notes and storing the reports for future use. Top of Page Resources The following Scholastic supplemental materials can be used in conjunction with Dirtmeister's Science Reporters: Big Books: Science (Grades K–4). This book series covers a variety of topics, from bugs to wind. They are brightly illustrated and great for the classroom library. Environmental Atlas of the United States, by Mark Mattson (Grade Levels 4 and up). The only environmental atlas for young readers that emphasizes U.S. ecological information. Be a Scientist skills books (Grades 3–6). This series includes featured scientists, hands-on activities, and an emphasis on practical process skills. The series consists of three sets of three books each for grades 3–4, 4–5, and 5–6. Quick and Easy Learning Centers: Science, by Lynne Kepler (Grades 1–3). This Professional Resource book focuses on the use of everyday materials to promote independent, hands-on learning. Information on how-tos, management, experiments, and reproducibles are included in this helpful book. Complete descriptions of these resources and more can be found in Scholastic's Supplemental Materials Catalog. You can also call Scholastic directly at 1-800-724-6527. Related Web Sites General Science Sites Science and Technology for Children Curriculum http://www.si.edu/nsrc/pubs/stc/overv.htm The Natural History Museum (London) http://www.nhm.ac.uk/index.html Edison National Historic Site http://www.nps.gov/edis/home.htm Endangered Species Program http://endangered.fws.gov/ National Inventors Hall of Fame http://www.invent.org/book/index.html Understanding Our Planet Through Chemistry http://minerals.cr.usgs.gov/gips/aii-home.htm Maps and References http://www.cgrer.uiowa.edu/servers/servers_references.html Dirtmeister's Home \| Simple Machines \| Teacher's Guide \| Kids' Sample Reports