Topic: Investigating Magnetism 4th Grade Time length: 60 minutes. Lesson Overview/Goals

Transcription

1 Topic: Investigating Magnetism 4th Grade Time length: 60 minutes Lesson Overview/Goals Students will explore the properties of magnetic energy. They will observe and identify the push or pull force between North and South magnetic poles in objects. Students will work in pairs to hide two magnets in a cardboard box. Another pair of students use detecting objects to determine the location of the hidden magnets. These detecting objects include a plate of iron filings, a paperclip, and a steel screen. Students will also work with the magnetic properties of a compass. Students will observe and know that magnetism is an invisible force that can go through objects and that iron and steel can be used to detect a magnetic field. Students will also practice using and defining terms including attract, repel, and force. Essential Questions What is magnetism? What are characteristics of a magnetic field? How does magnetism interact with matter, especially metals like iron? What can magnetic energy be used for? What is a force? What is energy? How is magnetism applied in society and technology? Key Content Highlights: Iron and steel (which has iron in it) are metals that attract magnets. Magnets have a North and South pole. N-N= repel, S-S=repel, N-S=attract Magnetism is a natural energy. The earth is in a magnetic field with two opposing poles. Future lessons can explore how a compass works, where the magnetic field of earth begins (the core) and ends.. how magnetism works in our atmosphere/outer space How humans harness magnetic energy for practical purposes, like the Maglev train which runs on magnetic energy in China and Germany

2 Real World Application Recognizing magnetism as a natural phenomena on earth: understanding of how magnetic energy interacts with atoms, organisms, the planet and its atmosphere, other celestial bodies Magnetism in society/technology: extension of concept comes from discussing and viewing a video on the Maglev train, an emerging infrastructure innovation that utilizes electromagnetic energy for high-speed travel Magnetism in daily life: understanding of science process in everyday objects like refrigerator magnets Practical purposes: understanding of how a compass works Objectives Students will be able to: Explain that iron and steel attract magnets. Differentiate attracting and repelling magnetic forces and why (opposite poles). Explain that magnetism is an invisible force that can go through objects. Utilize iron to detect a magnetic field. Next Generation Science Standards 3-PS2-3 3-PS2-4 Ask questions to determine cause and effect relationships of electric or magnetic interactions between two objects not in contact with each other. Define a simple design problem that can be solved by applying scientific ideas about magnets. PS2.B- Disciplinary Core Ideas about above standards:

3 Types of Interactions: Electric and magnetic forces between a pair of objects do not require that the objects be in contact. The sizes of the forces in each situation depend on the properties of the objects and their distances apart, and for forces between two magnets, on their orientation relative to each other. Academic Language - Magnetism - Detection - Properties - Attract (attraction) - Repel (repulsion) - Force - Investigate - Observe (observations) - Device - Explanation - Conclusion Assessment Overview Formative assessment of students conceptual understanding occurs through conversation and questioning throughout experiment. Students will successfully use iron to detect the location of hidden magnets. Students will also explain in writing about their observations, how they knew the magnet s location, and why one detection device would be more useful than another to detect a magnetic field. Post-experiment recordings and reflections will be used as evidence to evaluate knowledge of key terms and concepts. Materials Needed - 13 Cardboard boxes - Tape - 26 Magnets - 13 Steel screen - 13 Iron filings on a paper plate in a sealable plastic bag - 13 Paperclip - 13 Compass - 26 Worksheets - Overhead Projector to view video on Maglev train to reinforce concepts of attraction and repulsion Advance Prep: Assemble boxes and iron filings, prepare materials and hand-outs

4 The Learning Plan: The 5E Model Engage 5 minutes Review magnetic facts and observations gained so far Can you think of a general rule about what magnets stick to? What is a force? Push or a pull. Attract= pull Repel=push What does it mean to detect something? You are acting like a detective. It means to find something by using clues. Explore 30 minutes Students will work in pairs to hide magnets and determine their location by detecting the magnetic field through the use of varied iron objects and a compass Students will explore the properties of magnetism by observing how different objects interact. Students will make observations, compare and contrast materials, and develop new questions and answers about magnetism and metals Steps: 1. Elbow partners at each table decide which Team is 1 and Team 1 will be the magnet hiders and 2 will be the magnet detectors. 3. Using this box, Team 1 will pick two spots inside the box to tape the magnets while Team 2 is not looking. Team 1 can pick anywhere inside, on the bottom or a corner, or on the sides. 4. Team 2 will use the iron objects to see if they can find where the other pair hid the magnet. Teams swap roles as hider and detector. 5. Record on the drawing where the magnets where and explain your thoughts and observations on the handout. Explain 35 minutes Discussion while exploring: How did you know the magnet was there? Which detection device worked the best? Why do you think so? What is happening here? Why do you think it is sticking? What is a science word for sticking? Instructor will reinforce to students through direct teaching and follow up questioning that when they find the iron objects to be sticking this behavior means there is an invisible force of attraction. If the magnets were trying to resist each other, this is called repelling. Instructor can visit each group and encourage students to explain the difference using their observations and data.

5 Students will construct explanations on paper and through discussion. Elaborate/Extend 15 minutes Share videos on the Maglev Train, and how it applies the same forces we learned about in class Just like how our magnets repelled when the poles are the same, the bottom of the train and the track have the same magnetic poles.. this magnetic energy is made by electricity and is very strong so the train floats! There is no friction so the train can go very fast Evaluate Evaluation of Detecting Magnets handout: Explain how you know the magnets are there Record observations Which device worked best to detect and why do you think so? High understanding: - Did the student accurately use the term attract to explain the magnetic interactions - Did the student connect the movement of the iron particles and sticking of iron as a sign of magnetism? - Can the student identify that iron and steel are magnetic materials? - When the iron pieces started moving, I knew it was attracting the magnet. Some understanding: - Did the student connect movement of iron particles as a detection of a magnetic field? You can see it move. It is invisible - Did the student observe sticking as a sign of magnetic energy? Low understanding/cannot determine student understanding yet: - Did the student fail to provide magnetism content in their written explanation? - Did the student mis-use key terms or concepts?

6 - We slided the magnet around so we can detect where the magnet were hidden Modifications - Students worked in an inclusionary science setting, with mixed pairs of students with and without IEP s - Instructor reinforced directions and content through small-group questioning and follow-up - Instructor and peers reinforced directions and science understanding in native language Gujarati for ELL s As students explore and discuss findings, compile what we are learning on the board and on content chart to make new vocabulary and content accessible to all students. Investigating Magnetism attract= pull together - poles are opposite (North and South) repel= push apart - poles are the same (S-S or N-N) Record facts that students provide during review, exploration, wrap-up: - Magnetism is an invisible force - Can go through things like desks and cardboard boxes, spacers - Affected by space between them (power of magnetism decreases as space increases between two magnets) - Iron can be used as a detector

7 Student Work A:

8 Student Work B:

9 Student Work C: