afbcad68c008218de7e13d954959db8e.ppt
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Teaching Science for Motivation and Understanding Discussion with Knowles Fellows November, 2003 Andy Anderson and Gail Richmond
Issues You Would Like to Discuss
Watching Jim Minstrell Teach about Newton’s Laws of Motion • What do you notice that would cause you to change your answers to some of the questions about moving objects? • What did you notice that would cause you to change or add to your answers to questions about problems of practice? • What did Jim Minstrell need to know in order to teach this way?
Problems of Practice in Science Teaching 1. Science content: Goals and activities for student learning 2. Students and assessment 3. Classroom learning environments and teaching strategies 4. Professional resources and relationships
Niels Bohr on Scientific Reasoning The task of science is both to extend our experience and reduce it to order, and this task represents various aspects, inseparably connected with each other. Only by experience itself do we come to recognize those laws which grant us a comprehensive view of the diversity of phenomena. As our knowledge becomes wider we must always be prepared, therefore, to expect alterations in the points of view best suited for the ordering of our experience.
Extending Experience and Reducing It to Order Deepest scientific theories Sense Experience Extending experience Reducing experience to order Pursuing the “turtles all the way down”
Piaget on Children’s First Inquiry: Developing a “Theory of Objects” • Babies: Selective attention to faces, motion, unusual stimuli; no continuing interest when something disappears from view • Peek-a-boo: Experience with objects disappearing and reappearing; encouraging adults to play • Hide and seek: Finding hidden objects • Object permanence as eventual outcome
Piaget on Conservation of Liquids • Extending experience by pouring liquids from one container to another • Early focus on only width or depth: More liquid in deeper container • Later: coordinating thinking about width and depth • Final: conservation of liquids; volume is always the same regardless of container
Experientially Real Objects, Systems, and Phenomena Edge of accepted experience Experiences taken for granted as “real” Explanations for those experiences Deepest scientific theories Sense Experience Extending experience Reducing experience to order
Development of Knowledge • Extending experience: Adding to our stock of “experientially real” objects, systems, and phenomena – Adding new sense experiences – Adding vicarious sense experiences (e. g. , pictures, video) – Adding believable, experientially real data (e. g. , measurements, carefully recorded observations) • Reducing experience to order: Developing new and better models and theories – Conceptual change: Replacing old theories with new ones that account for more data – Converting previous “theories” to taken-for-granted experientially real objects, systems, phenomena (e. g. , existence of objects, conservation of liquid volume)
Why Extending Our Experience and Reducing It to Order Isn’t Always Science Multiple Sense-making Strategies
What Counts as Experientially Real? • Everyday judgments: Seeing (or hearing, touching, feeling) is believing – Vividness and immediacy of experience – Confirmation by peer group • Scientific judgments: Creating data from experience – – Reproducibility Precision Provenance of records Confirmation by skeptical observers
Times When Everyday and Scientific Judgments Differ • • Rumors News, history Religious experience Data collected with complicated instruments • Data presented in difficult-to-understand formats
What Counts as a Good Model or Theory? • Procedural display: Whatever it takes to get a good grade • Practical reasoning: Whatever it takes to get practical results (including inventing things) • Narrative/metaphorical reasoning: Stories or metaphors that bring coherence to our experiences (including news, history) • Model-based reasoning: Models that account for all relevant data in testable, parsimonious ways – “Unbroken chain of connections” from data to models – Consistency with other models and theories
Model-based Reasoning: Scientific Inquiry and Application
Content Example: Newton’s Laws What does it mean to “understand” Newton’s Laws?
Historical Sense-making Strategies for Explaining Motion • Aristotle, Ptolemy, and Aquinas • Setting the stage for Galileo: Impetus theorists and Copernicus • Galileo • Newton
Aristotle, Ptolemy, and Aquinas • Practical reasoning: Moving objects with simple machines, throwing, pushing, bows and arrows • Narrative reasoning: Where and why do objects move – Animate objects (animals) move on their own – Natural motion: Inanimate objects tend toward their own spheres (earth, water, air, fire) – Violent motion: Animals can impart motion to inanimate objects – Heavenly objects are kept in motion by the Prime Mover – Aquinas: Prime Mover is Christian God • Model-based reasoning: Ptolemaic system explains motions of sun, moon, planets
Setting the stage for Galileo • Practical reasoning: Siege engines (catapults, trebuchets, cannon); accuracy depends on direction and speed (not just personal skill) • Narrative reasoning: Protestant reformation emphasizes personal God rather than distant Prime Mover • Model-based reasoning: Copernicus suggests sun-centered model that fits observations better
Galileo • Practical reasoning: Inventing better telescopes, measuring speed and direction of rolling and falling objects • Narrative reasoning: – Challenging Ptolemy and Aquinas: Copernicus’ model is true, not just way to calculate positions – Telescopic observations of corruptible heavens • Model-based reasoning: Mathematical predictions of speed of falling objects
Newton • Practical reasoning: Mathematical predictions of trajectories (models improve practical reasoning rather than the other way around) • Narrative reasoning: – Anti-Trinitarian Biblical text criticism: God does not intervene in everyday events – Newton’s apple: The apple and the moon are following the same laws • Model-based reasoning: Newton’s Laws of motion and universal gravitation
Newton’s First Law Traditional wording Contrasting Newton and Aristotle • Every object continues in a state of rest, or of motion in a straight line at a constant speed, unless it is compelled to change that state by unbalanced forces exerted on it. • Motion doesn’t need to be explained, only changes in speed or direction (velocity). • Necessity: No forces or balanced forces always mean no change in speed or direction, and vice versa.
Newton’s Second Law Traditional wording • The acceleration produced by a net force on an object is directly proportional to the magnitude of the net force, is in the same direction as the net force, and is inversely proportional to the mass of the object (F = ma). Contrasting Newton and Aristotle • Forces do not cause motion. Instead they cause acceleration, or change in speed or direction (i. e. , velocity).
Newton’s Third Law Traditional wording • For every action there is an equal and opposite reaction. Contrasting Newton and Aristotle • Forces always come in pairs. When A exerts a force on B, B exerts an equal and opposite force on A. This does not mean that the forces on A or B are balanced.
Aristotelian and Newtonian Answers to Questions 1. Book on the table • • Aristotelian: Table blocks book from falling Newtonian: Table exerts an upward force that balances the downward force of gravity 2. Coin in the air • • Aristotelian: Coin’s upward flight is sustained by a “force from the hand” Newtonian: Continuing upward motion doesn’t need to be explained. Unbalanced force of gravity slows the coin down.
Aristotelian and Newtonian Answers to Questions (cont) 3. Cart at constant velocity • • Aristotelian: Continued motion requires continued force Newtonian: Net force is 0 for motion at constant speed and direction 4. Accelerating cart • • Aristotelian: Increasing motion requires increasing force Newtonian: F = ma. Constant acceleration requires a constant net force
Problems of Practice in Science Teaching 1. Science content: Goals and activities for student learning 2. Students and assessment 3. Classroom learning environments and teaching strategies 4. Professional resources and relationships
Purposes for Classroom Assessment • Understanding your students • Helping your students to assess and improve their own understanding • Grading
Criteria for Assessments that Help You Understand Students • Connection to goals: The questions address important objectives you have for student learning • Interesting wrong answers: Even incorrect answers reveal students' thinking • Insight into students’ sense-making: The students’ answers help you understand how they make sense of the world, not just where their knowledge of science is weak. • Starting a dialogue with students: The questions help you to start discussions with students where they can compare their ideas with scientific ideas.
Types of questions that produce interesting wrong answers
Backwards reasoning • If --- is the answer, then what was the question? • What question were scientists trying to answer: – …when they discovered photosynthesis? (e. g. , why do plants need light? ) – …when they discovered atomic theory (e. g. , why do elements always combine in certain proportions? )
Familiar situations • Getting students’ theories about familiar examples. – What are the forces on a coin flipped into the air? – Are your eyes the same color as your mother’s? How do you think that happened? – What’s inside the bubbles of boiling water?
Connecting different representations • Seeing what happens when students represent the same example in different ways. – Draw a picture of what is happening to the atoms of Na. Cl as solid salt dissolves in water. – Show the light rays travel that enable a person to see a tree as she looks out the window.
Short answer + explanation • Ask students to make a choice or draw arrows, then explain their reasoning. – Does food normally move up or down a plant’s stem? Explain your reasoning. – Will the “ashes” left after magnesium burns weigh more or less than the original metal? Explain your reasoning.
Use misconceptions research • Ask questions that will reveal common misconceptions (as reported in research). – What question would reveal a belief that liquids disappear when they evaporate? – What questions would reveal a belief that plants get their food from the soil? – What question would reveal a belief that the phases of the moon are caused by the earth’s shadow?
Comparing examples or concepts • Ask students to compare and contrast different real world examples or familiar terms – heat vs. temperature – force vs. momentum – Current vs. voltage – Green plants vs. fungi – Volcanoes vs. other mountains
Critique of suggested responses • Ask students whether they agree or disagree with responses that reveal misconceptions, and why. – My friend says that sunlight is food for plants. Do you agree? Why or why not? – My friend says that when water evaporates, the water vapor weighs just as much as the liquid water. Do you agree? Why or why not?
Teaching Newton’s Laws to (Aristotelian) High School Students • Describing motion: Focusing on speed and direction rather than destination and reason for motion • Negotiating standards for what counts as evidence (“experientially real”) • Extending experience: Collecting data in situations where Aristotle’s rules break down • Questioning students’ narrative and practical knowledge • Model-based reasoning: Finding consistent, parsimonious explanations that fit all the data • Quantitative rigor: Using models to make precise, quantitative predictions
Watching Jim Minstrell Teach Again How does he address each of the challenges to his students’ learning with understanding?
Problems of Practice in Science Teaching 1. Science content: Goals and activities for student learning 2. Students and assessment 3. Classroom learning environments and teaching strategies 4. Professional resources and relationships
Approaches to Teaching Science (from Mark Olson) Carol: Science Curriculum as a Progression of Models Jennifer: Science Curriculum as “Chapters in the Story” Bar magnets Example Electromagnets Example Magnetic Induction Example Ferromagnetism Example Magnetic Domains Example Problems with Carol’s approach: Problems with Jennifer’s Approach: oversimplified models leaves out the good part not part of Kuhn’s normal science students can only tell story no model-based reasoning students forget what they studied
General Teaching Strategies • Covering content: Telling the story with examples and expecting students to tell it back (Jennifer’s approach) – Leads to narrative understanding or procedural display • Learning cycles focusing on application of model -based reasoning (Carol’s approach) • Inquiry cycles focusing on developing new models through reasoning about data (Minstrell’s approach)
Classroom Environments for Learning and Inquiry Cycles • Personal and emotional safety for students, including moderate levels of risk and ambiguity • Motivating students to learn: Expectancy times value • Social norms for participation and communication
Model-based Reasoning: Scientific Inquiry and Application
Learning Cycles
Transfer of Responsibility in the Learning Cycle
Stages in the Learning Cycle • Establishing the problem: Connecting with prior knowledge and establishing motivation to learn • Modeling: Exposing learners to comprehensible models of good practice • Coaching: Providing opportunities for practice with scaffolding or support • Fading: Gradually removing support until learners engage in the practice independently • Maintenance: Continuing practice after initial learning is over
Prerequisites for Successful Learning Cycles (Focused on Application) • • • Model or theory that you want students to be able to apply Set of real-world examples Pattern for students to follow in applying theory to examples
Important Points about Learning Cycles • Assessing student thinking. Include embedded assessment that will help you and your students understand their ideas and practices—both correct and incorrect. • Keeping the objective whole. Students work through several examples where they see or do the whole task. • Learning as transfer of responsibility. Students take more responsibility for doing the task. • Scaffolding is temporary. Learning cycles are complete when students can accomplish the objective on their own.
Inquiry Cycles
Essential Features of Classroom Inquiry 1. Questions. Students engage in scientifically oriented questions. 2. Evidence: Data and patterns. Students respond to questions by looking for patterns in data—their own experiences and/or data supplied by the teacher. 3. Students’ explanations. Students formulate explanations from evidence. 4. Scientific theories or models. Students compare their explanations to explanations based on canonical scientific models or theories 5. Communication: Argumentation and justification. Students explain and justify their methods, results, and conclusions.
Prerequisites for Successful Inquiry Cycles • Experiences: “Experientially real” data from students’ personal experience, classroom observations, simulations, or archived data sets • Pattern(s) in experience that students will be able to see • Theory or model that explains patterns
Lab Activities that Are Not Inquiry 1. Confirmation labs: students follow directions. Purposes: Practicing lab techniques Confirming accuracy of laws and theories 2. “Consumer reports” labs: students compare products or practices to find the best one. Purposes: Reasoning about and developing experimental techniques Practicing evidence-based argumentation and decision making 3. Explanation labs: students observe phenomena, then use models and theories to explain what they saw. Purposes: Connecting representations at different levels of abstraction Practicing detailed explanations of real-world examples 4. Design labs (engineering inquiry): students use scientific principles to design systems that accomplish specific purposes (e. g. , egg drop lab, building bridges, maximizing crop yield). Purposes: Applying scientific theories to practical design problem. Building engineering skills
Inquiry Activities 1. Naturalistic or field inquiry: students look for patterns in observations that they make. Examples: Geological or ecological field work Astronomical observations, such as sun and moon 2. Experimental inquiry: students create new experience in the lab, often with planned variation. Examples: Systematically observing products of different reactions Comparing plant growth under different conditions 3. Data analysis: students look for and explain patterns in “experientially real” data sets that are given to them. Examples: Looking for patterns in weather or geographic data Explaining reported results of dangerous experiments 4. Simulations: students look for patterns and explain results in “virtual worlds” that imitate reality. Examples: Models of moving objects or electrical circuits Ecosystem models
Learning and Inquiry Cycles • Prerequisites • o Model or theory o Set of real-world examples o Pattern for students to follow in applying theory to examples • Stages or activities o o o Establishing the problem Modeling Coaching Fading Maintenance Prerequisites o “Experientially real” data o Pattern(s) that students will be able to see o Theory or model that explains patterns • Activities o Questions o Evidence: Data and patterns o Students’ explanations o Scientific explanations o Communication
Jim Minstrell’s Teaching Strategies • Classroom environment • Learning cycles • Inquiry cycles
Problems of Practice in Science Teaching 1. Science content: Goals and activities for student learning 2. Students and assessment 3. Classroom learning environments and teaching strategies 4. Professional resources and relationships
Key Issues in Professional Resources and Relationships • Finding, using, and adapting resources • Learning from imperfect mentors • Using assessment to learn from experience • Explaining yourself and your practice to colleagues, administrators, parents
Revisiting Questions What else do we need to discuss?
Contact Us • Andy Anderson – andya@msu. edu – 319 A Erickson Hall, Michigan State University, East Lansing, MI 48824 – 517 -432 -4648 • Gail Richmond – gailr@msu. edu – 319 Erickson Hall, Michigan State University, East Lansing, MI 48824 – 517 -432 -4854 • Website: http: //Sci. Res. educ. msu. edu/TEScience/index. htm