Measuring Static Electricity Grade Level: 4-­‐5 Time: Approximately 2.5 hours By: Carrie D. Perry (Bedford County Public Schools) This lesson extends students’ understanding of magnetism and electricity through a structured inquiry on static electricity. Students make predictions about different materials and their ability to generate static. The students will use a balloon to test the materials’ ability to generate static and will test the strength of the static charge as they pursue an answer to the question: What effect does the material used to create static have on the strength of the charge? This lesson was developed through the “Introduction to Inquiry: A Professional Development Model to Reform Teacher Practices” project directed by Science by Inquiry at Sweet Briar College and funded by the Virginia Department of Education Math Science Partnership Grant (MSP) 2012-­‐2013. Measuring Static Electricity Page 1 Objectives Know o
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static electricity electric charge attract and repel positive, negative Understand o Extended contact (like rubbing) between surfaces can allow charges to move from one item to another creating an imbalance of negative and positive charges. The build up of these negative or positive charges can attract or repel other objects. Some materials naturally lend themselves to easily losing or gaining these charges. Do o
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Create a build up of static using different materials Observe the type of action (attract or repel) Quantify the strength of that action Represent numerical data in a graph “I feel very strongly that inquiry-based learning meets the needs of students with learning disabilities and
attention issues. It allows these kids to exhibit strengths that academic tasks often do not showcase. In the
future, I know that how I plan any lesson will be influenced by Inquiry as a style of teaching and as a core
philosophy of what really works.”
~ Carrie Perry
Measuring Static Electricity Page 2 Standards Virginia Standards Science 4.1 The student will demonstrate an understanding of scientific reasoning, logic, and the nature of science by planning and conducting investigations in which a) distinctions are made among observations, conclusions, inferences, and predictions; b) objects or events are classified and arranged according to characteristics or properties; e) predictions and inferences are made, and conclusions are drawn based on data from a variety of sources; f) independent and dependent variables are identified; g) constants in an experimental situation are identified; h) hypotheses are developed as cause and effect relationships; i) data are collected, recorded, analyzed, and displayed using bar and basic line graphs; j) numerical data that are contradictory or unusual in experimental results are recognized; k) data are communicated with simple graphs, pictures, written statements, and numbers; Science 5.1 The student will demonstrate an understanding of scientific reasoning, logic, and the nature of science by planning and conducting investigations in which d) hypotheses are formed from testable questions; e) independent and dependent variables are identified; f) constants in an experimental situation are identified; g) data are collected, recorded, analyzed, and communicated using proper graphical representations and metric measurements; h) predictions are made using patterns from data collected, and simple graphical data are generated; i) inferences are made and conclusions are drawn; Science 4.3 The student will investigate and understand the characteristics of electricity. Key concepts include: c) static electricity Science 5.3 The student will investigate and understand that matter is anything that has mass and takes up space and occurs as a solid, liquid or gas. Key concepts include: c) atoms and elements (key vocabulary includes protons, neutrons and electrons.) National Science Education Standards Students should know, understand and use concepts, facts and principles of light, heat, electricity and magnetism. Measuring Static Electricity Page 3 Context and Background Information This lesson will be the next to last lesson in the electricity and magnetism unit. Prior to this activity, the students will have learned about magnets, including the meanings of words such as attract, repel, and opposites, and will be familiar with the concept of negative and positive. Students will be pre-­‐assessed to determine their familiarity with insulators and conductors since these words will be brought up in our discussion of the materials being used for the experiment. Other key concepts needed for this lesson include basic understanding of constants and using a timer and a calculator. In addition, students need to have knowledge about graphing information using a bar graph. A follow up lesson will also include a connection to natural static (lightning) which will segue nicely into the last portion of the unit, famous contributors to our modern understanding of electricity. The key objectives for this lesson are for the students to gain a better understanding of how static is formed and how extended contact (like rubbing) allows charges to move from one item to another creating an imbalance of negative and positive. They will also learn that a build-­‐ up of these negative or positive charges can attract or repel other objects. The students will see that some materials naturally lend themselves to easily losing or gaining these charges. This lesson is a structured inquiry with both the question and the method being provided by the teacher. The question for investigation is “What effect does the material used to create static have on the strength of the static?” Students will complete the procedures, record data, and generate their thinking map within their small groups. They will also report and analyze the data and draw conclusions on their own. “In the design of this experiment, it was very important to provide clear connections from the previously
taught material and to guide the students through to the question. One of the strengths of this lesson was the
simplicity of the experiment. The set-up, materials, planning and clean up were all easily managed and fun
to do. I also found that the students loved the video introduction and genuinely seemed interested in working
like a scientist to find answers to a question.”
~ Carrie Perry
The Triboelectric series Atoms, the building blocks of matter, contain positively (+) charged protons and negatively (-­‐) charged electrons. In many instances, the number of electrons is exactly equal to the number of protons; and thus, the overall charge is neutral. When objects rub together, there is a possibility for electrons to transfer from one object to the other. Some materials are more inclined to transfer their electrons than others. Objects that are more likely to transfer their electrons are called conductors; objects that are less likely to transfer their electrons are called insulators. As electrons are transferred from one object to another, one object become more negative (it is gaining electrons) while the other object becomes more positive (it is losing electrons). These objects will then be attracted to each other similarly to the way opposite poles on a magnet attract each other. The charge created by rubbing two objects together is called triboelectric charge, or static electricity. Measuring Static Electricity Page 4 When a balloon is rubbed against human hair it causes the hair to become positively charged and the balloon to be negatively charged. When they are separated, the opposing charges between the hair (+) and balloon (-­‐) will cause them to attract to each other making the hair stand up. Individual hairs, all being positive, repel each other (like same charged poles between magnets) which is why it seems that the individual strands of hair stick out. Static electric shock is the opposite. Shock occurs when charged objects transfer electrons quickly to become neutrally charged again. A chart of objects that shows if they are more likely to become positively or negatively charged is called a triboelectric series. This series can be used to determine which objects will create charges when rubbed together. The further apart on the triboelectric series two objects are, the stronger the triboelectric charge they will create when they are rubbed across each other. Measuring Static Electricity Page 5 What You Need Per group of 4 students: 
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paper plates circle template, 2 inches in diameter marker balloon balloons should be freshly-­‐inflated to similar size, see “Getting Ready” paper confetti dots (2 tsp per group) confetti dots are made with paper and a hole punch, see “Getting Ready” glass plate paper towel old T-­‐shirt pizza or cookie sheet calculator timer or stopwatch For each student:  Modified KWL chart (Appendix B)  Data Recording Sheet (Appendix C) Measuring Static Electricity Page 6 Getting Ready About 10 days before the activity and leading up to the inquiry during the magnetism unit: About 10 days before the inquiry lesson is to begin, during the unit on magnets, give a short pre-­‐lesson assessment in the form of an Exit Card (Appendix A). The pretest asks students to describe static in their own words and share an experience that they have has with static in an illustration, and has two vocabulary-­‐specific multiple choice questions about students’ understanding of the words attract and repel. The days leading up to the lesson, have the students use bar graphs to plot data. Include an informal assessment (observation) of student work on each student’s understanding of graphing. The results from these assessments will be used to group students into like-­‐ability groups and establish a baseline for measuring growth. Before the day of the activity Make confetti dots using a hole punch and plenty of regular copy paper. Make copies of all needed handouts (Appendices B and C). Morning of the investigation Inflate balloons to similar size. Measuring Static Electricity Page 7 Day One: Planning the Investigation Engagement The teacher will present the class with a KWL chart and review the principles of magnetism that have already been covered. Then, open the discussion with a question, "When are some other times that we actually see the words attract and repel demonstrated in life?" After some discussion, show a video of kids playing on the trampoline and have the students determine why the girl's hair is standing on end. After the students have mentioned static electricity, we will decide if her hair is demonstrating attract or repel. The students will be grouped (by pre-­‐assessment results) and given balloons to explore for a period of time. During the exploration, students will be prompted to generate their own static electricity results by rubbing the balloon on their hair. Information that is shared will be added to the “K” column of the KWL chart as a group. Explain to the class that in tomorrow’s investigation, they will be investigating materials and static charge. Quickly show the students how rubbing the fabric on the balloon can charge the balloon and how the static charge will attract a few paper confetti dots. For an exit ticket, hand out an index card, and have each student: Write his/her name; Write a statement about static electricity using either the word attract or repel in the sentence; Write at least three materials that they are interested in testing. Collect these cards. To prepare for tomorrow’s investigation, use the students’ index cards to divide the class into 4 groups of 4-­‐5 students. Group the students based on the pretest results: students who demonstrate the most knowledge, kids with moderate understanding, and kids with the least knowledge. This will probably not align with their ability levels in academics, but with how well they have retained and generalized the previously taught lessons. It will also prevent the stronger students from taking over the experiment. Some Inquiry lessons work better with a less homogeneous mixture of students, but this particular lesson seems to lend itself to the tiered groups. “The structured lesson was an experience for both me as the instructor and the students. Most importantly,
they will remember important information because they are able to tie it to a hands-on experiment and
memory. I will also remember the information because I was experiencing it with them. The time invested in
preparation for the lesson also taught me additional information about static that I found fascinating. My
enjoyment was contagious to the students as well. They were able to see that learning was fun for an adult.”
~Carrie Perry
Measuring Static Electricity Page 8 Day Two: The Investigation
Introduce the Investigation Pose the question for investigation and provide procedures and materials: “What effect does the material used to create static have on the strength of the static?” Each group will give a prediction about the materials and the results that will be added to the KWL (W) on the SmartBoard. The teacher will provide the materials and method for the investigation: Each group (see grouping information on previous page) will receive from the teacher 1 paper plate, 1 circle template, a marker, a balloon, paper confetti dots (approximately 2 tsp per group), a glass plate, an old T-­‐
shirt, a pizza pan or cookie sheet, a calculator, a timer or stopwatch, and a data collection log/bar graph template handout. Carry Out the Investigation Working in groups, students will trace a circle onto a paper plate and pour their confetti dots into the circle on the paper plate. Using the stopwatch, they will rub the balloon against the materials provided (ie. glass plate, metal pan, etc.) for ten seconds and then hold the balloon about 1 inch above the small pile of dots. They will count the dots picked up (and hopefully note that some jumped off the balloon almost as soon as they were picked up) and then repeat the test. Each material should be tested and results recorded 3 times. While the students are conducting their investigation, the teacher should circulate around the room, primarily to observe, but also to take note of students who may need encouragement. Students may need prompting to keep the closeness of the balloon (to the plate) the same each time, others may need reminders to by keeping count on their individual record sheets-­‐ not just sitting by, and some students may need modeling from the teacher of how to record their results. Note: If the experiment takes more than one day to complete, new balloons must be used each day. Organizing and Analyzing Data After the results are recorded, the group will use a given template to graph the average of the results. Some assistance will be given at this juncture with the definition of average and students will be allowed to use a calculator. Students will then use the bar graph to support/disprove their findings as begun on the KWL, and complete the L column as a multi flow thinking map for their presentation. Measuring Static Electricity Page 9 Days Three: Data Analysis Making Meaning of the Investigation Experience For the wrapping up portion of the lesson, students will present their findings in their groups. During the presentations, classmates will score their peers’ presentations using a rubric (Appendix D). When all teams have presented, the teacher will ask some follow up questions: • How is static somewhat like a magnet? • Did we notice a difference in materials that are conductors vs. insulators? • What do you think the results would be if we did this experiment in a damp place? The teacher will also show the students that even water can be affected by static. Demonstrate or show pictures of a stream of water bending in response to a static charged balloon. The teacher will pull up Internet resources about the Triboelectric Series and use pictures on the SmartBoard to show atoms with emphasis on protons and electrons and discuss how this impacts the outcome (attract vs. repel). Discuss the students’ results in terms of a triboelectric series – what materials had the most effect? Which materials had less effect? Could our results be organized into a series? How do our results compare with the one shown here? After the lesson is complete, the following day we will connect static to lightning and then on to famous contributors to the field of electricity such as Benjamin Franklin and Michael Faraday. The post assessment will be contained within the Benchmark test at the end of the unit. “The objectives were well suited to the students. The concepts of electricity and magnets are a huge part of
the fourth grade science curriculum. The students were able to access the information with ease and made
connections to real life during the discussion times. I will remember three major things that I learned from
this experience: first, be flexible and allow that “wait time” for students to think about the information or the
question. Second, consider the environment and the staff that may be involved - utilize these effectively by
planning ahead and maybe even assigning tasks for the staff. And last, pace. I didn’t build in time for the
hiccups that occur in a hands-on activity. This caused parts of the lesson that were important to be rushed
and that, in turn, created problems with student noise level and classroom management.”
~ Carrie Perry
Measuring Static Electricity Page 10 Assessment Objectives The overall learning objective of this lesson (The Big Idea) is for students to make connections between electricity and the forces of attraction and repulsion. The use of confetti dots as a measure of the strength of the force will provide students with a concrete visual representation of that force. Learning goals also include: experimental design in the form of multiple trials; graphing and analyzing data to answer an investigation question; and collaboration and communication skills that lead to a deeper understanding of the nature of science. Assessment Plan •
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Students will be pre-­‐assessed for content understanding and grouped accordingly (Appendix A). During the activity, students will complete a modified KWL about static with the top "W" being our inquiry question: What effect does the material used to create static have on the strength of the static? After completing the activity, students will complete a thinking map as the “L” portion of the KWL and they will share their graphed data within small groups. Data will be collected and graphed by the students on a data recording sheet (Appendix C). Students will share both their data and the completed map with the class. The students who are not actively sharing will score their peers using a rubric (Appendix D). Additionally, the students' Benchmark tests will be examined by item to compare scores. The results from these assessments will demonstrate if the students understand the main vocabulary as well as if they understand the principles of static electricity. The thinking map in specific will show the final conclusions of the students and provide a connection for discussion about protons and electrons. The data collected and the data analysis on a graph will allow the teacher to assess the targeted math skills. Pre-­‐lesson Assessment During the teaching of the unit on magnets (about 10 days before this lesson), give a short pre-­‐assessment asking them to describe static in their own words and share an experience that they have had with static in an illustration. Two vocabulary-­‐specific multiple choice questions are also included to indicate students’ understanding of the words attract and repel. During math class in the days leading up to the lesson, the students use bar graphs to plot data. An informal assessment (observation) also provides information about the students’ understanding of graphing. The results from these assessments are used to group students in like-­‐ability groups and establish a baseline for measuring growth. Formative Assessments The students completed a modified KWL about static (Appendix B). The “K” portion of the chart contains a Thinking Map called a Circle Map. The students are allowed to list any information they already know about static or that they discover during the explore time. The “W” portion of the chart consists of the experiment question What effect does the material used to create static have on the strength of the Measuring Static Electricity Page 11 static? and then a space for listing predictions for the materials being tested. The predictions can be illustrated instead of written to show which students have a good grasp of attraction and static as key concepts. The “L” portion of the chart includes another Thinking Map called a Multi-­‐Flow Map. This type of graphic organizer lists several causes that lead to a single main even (which in this case was the static charge) and then leads out again to several additional effects which are more specific. These results are short phrases that are written as students complete the experiment as observations. “The students (and I) discovered that each team received slightly different outcomes when rubbing the
balloon on the different materials, but that everyone saw that the hair and the metal pan generated more
static pull on the paper dots than the glass or the cotton shirt. The teams shared these results using our
document camera and the SmartBoard and the other students rated their peers using a scale of 1-5 on the
steps, their record keeping, and their bar graph construction. The students especially enjoyed the chance to
give feedback about their peers’ work.”
~Carrie Perry
The teacher’s role during the inquiry is primarily to observe, monitor student involvement, and intervene when necessary. The teacher will also be taking note of students who may need encouragement to work with their team as a good teammate. Summative Assessments The students complete a multi-­‐flow thinking map (Appendix B). The results from this assessment will demonstrate if the students understand the main vocabulary as well as if they understand the principles of static electricity. The thinking map in specific will show the final conclusions of the students and provide a connection for discussion about protons and electrons. The data collected and the data analysis on a graph will allow the teacher to assess the targeted math skills. Students share both their data and the completed thinking map with the class. The students who aren’t actively presenting evaluate their peers using a rubric (Appendix D). The final piece of the assessment continuum is a data collection/ bar graph that each student will complete (Appendix C). “Overall, the students showed consistent understanding of all of the key concepts and also were able to draw
out the conclusion that other similar items (such as wool instead of hair, wood instead of glass) might
produce similar results. The students also noted in their presentations that certain steps had to be kept
exactly the same for the bar graphs to be “fair.” My favorite characteristic of this lesson, however, was that
everyone was able to contribute and all students were engaged.”
~Carrie Perry
Measuring Static Electricity Page 12 Acknowledgements YouTube static video: http://m.youtube.com/watch?v=ZeQoaEfiPlk Static for Kids: http://www.sciencemadesimple.com/static.html http://www.ducksters.com/science/static_electricity.php http://www.imcpl.org/kids/blog/?p=8925 More information on the Trioelectric series: http://www.sciencemadesimple.com/static.html http://esda.org/fundamentalsP1.html http://www.school-­‐for-­‐champions.com/science/static_materials.htm Llewellyn, Douglas. Inquire Within. Corwin Press, Thousand Oaks, California, 2007 Measuring Static Electricity Page 13 Appendices: Handouts 1. Pre-­‐Test 2. Modified KWL 3. Data Recording Sheet 4. Peer Presentation Rubric Measuring Static Electricity Page 14