Teaching as an Alternative Scientific
Transcription
Teaching as an Alternative Scientific
Teaching as an Alternative Scientific Pursuit Bill Wood Department of MCD Biology and Science Education Initiative University of Colorado, Boulder SDB Meeting Re-Boot Camp San Francisco, 7/23/09 How do you view your teaching currently? E.g. An unwelcome chore that gets in the way of my research? The most fulfilling part of my job as a faculty member? etc. Different views of teaching A way to find out more about how your students learn A new area of professional scholarly work? Two stories . . . Scientific Teaching - what is it? Set clear objectives for instruction Develop an assay for its effectiveness Develop methods for achieving objectives Refine methods based on assayed outcomes First story: The Science Education Initiative at U. Colorado, Boulder Five participating science departments: Chemistry and Biochemistry Earth Sciences Integrative Physiology MCD Biology Physics All strongly research-oriented All teaching many undergraduates SEI Goal: improve effectiveness of science teaching Process In each department, for each large course: • Establish specific learning goals through faculty consensus • Create validated assessments for measuring attainment of learning goals • Create and utilize pedagogically effective materials and teaching approaches that are: • aligned with the learning goals • based on educational research • improved each year based on assessment results Wieman's "Holy Trinity" 1. Establish specific learning goals through faculty consensus Learning goals (beyond the syllabus): • specify what students should be able to do by the end of each course • guide 60-70% of instruction (remainder discretionary) • Result: the departmental curriculum is redefined in terms of specific learning objectives, which can be assessed by performance-based criteria Aim for higher Bloom's levels ! Bloom's Levels of Understanding 6. Evaluation: think critically about and defend a position 5. Synthesis: transform, combine ideas to create something new 4. Analysis: break down concepts into parts 3. Application: apply comprehension to unfamiliar situations 2. Comprehension: demonstrate understanding of ideas, concepts 1. Factual Knowledge: remember and recall factual information Bloom's Levels of Understanding 6. Evaluation: think critically about and defend a position Judge, Justify, Defend, Criticize, Evaluate 5. Synthesis: transform, combine ideas to create something new Develop, Create, Propose, Design, Invent 4. Analysis: break down concepts into parts Compare, Contrast, Distinguish 3. Application: apply comprehension to unfamiliar situations Apply, Use, Compute, Solve, Predict 2. Comprehension: demonstrate understanding of ideas, concepts Restate, Explain, Summarize, Interpret, Describe 1. Factual Knowledge: remember and recall factual information Define, List, State, Name, Cite Adapted from Allen, D. and Tanner, K., Cell Biol. Educ. 1: 63-67 (2002) Bloom's Levels of Understanding 6. Evaluation: think critically about and defend a position What students really need to learn how to do! 5. Synthesis: transform, combine ideas to create something new 4. Analysis: break down concepts into parts Some, but not many questions on MCAT, GRE exams 3. Application: apply comprehension to unfamiliar situations 2. Comprehension: demonstrate understanding of ideas, concepts Most questions on introductory biology exams! 1. Factual Knowledge: remember and recall factual information Example from our introductory genetics course Syllabus: Patterns of Mendelian inheritance Pedigree analysis Modes of inheritance Learning goals: After completing this course, students should be able to: 1. Analyze phenotypic data and deduce patterns of inheritance from family histories. Course level (one of 9 course-level learning goals): a) Draw a pedigree based on information in a story problem. b) Distinguish between dominant, recessive, autosomal, Xlinked, and cytoplasmic modes of inheritance. c) Calculate the probability that an individual in a pedigree has a particular genotype. Topic level (3-5 topic-level goals for each courselevel goal): (All Bloom's Level 3 or higher) 2. Create validated assessment tools for measuring attainment of learning goals These assessments: • are aligned with learning goals • validated through student interviews, input from outside experts, and statistical analysis of results from large numbers of students • are administered as pre- and post-tests, to measure normalized learning gain <g> = 100 x (post-test - pretest / 100 - pretest) Now you're in a position to do Scientific Teaching! In the literal sense: Make course changes, introduce innovative approaches, and measure the effects on learning. 3. Create and utilize materials and teaching approaches proven to be pedagogically effective All involve Active Learning activities in addition to or in place of lecturing that: • are cooperative, involving students working in groups • are coupled with immediate feedback • require students to recall, think about, apply, and verbalize important concepts, rather than simply record facts for later memorization. Theory behind why active learning works Alternative views of education Transmissionist vs Constructivist • I know a lot about this topic, and you need to learn it, so I will transmit my knowledge to you by telling you about it. • I know a lot about this topic that you need to learn about, and I also know something about how people learn, so I will create situations and present challenges for you that will make it easier for you to efficiently construct knowledge about this topic for yourself. Evidence for the constructivist view is compelling, yet most large courses are still taught using a transmissionist approach. Some examples of constructivist activities in class: • Clicker questions (challenging, with peer discussion) • Concept mapping • Problem solving (in groups) • Analysis of case studies (in groups) • Analysis and explanation of research data All can help answer the question, for the student or the instructor: How am I doing ?? (formative assessment) Clickers Maternal-effect lethal mutants P0 +/+ F1 m/+ F2 F2 embryo will: +/+ live mutagenize Question: If m is a strict maternal-effect recessive mutation: A) m/m embryo will live. m/+ live m/m B) m/m embryo will die. ? An example of a clicker question, following a 20-minute lecture explanation of the physiology behind maternal effects of many embryonic lethal C. elegans mutations. Maternal-effect lethal mutants P0 +/+ F1 m/+ F2 F2 embryo will: +/+ live mutagenize A) m/m embryo will live. m/+ live initial individual answers n=70 Question: If m is a strict maternal-effect recessive mutation: m/m B) m/m embryo will die. ? Typical result, every year, in our developmental biology course. What to do, when half the class doesn’t get it? Best strategy: Let students debate the question and then re-vote. Maternal-effect lethal mutants P0 +/+ F1 m/+ F2 F2 embryo will: +/+ live mutagenize A) m/m embryo will live. m/+ live initial individual answers n=70 Question: If m is a strict maternal-effect recessive mutation: m/m B) m/m embryo will die. ? after group discussion Peer instruction works! E. Mazur, Peer Instruction, A Users Manual, Prentice-Hall, 1996) Don't forget to discuss what happened! interact with Concept mapping Transcription Factors interact with RNA Polymerase catalyzes activate or inhibit bind to binds to the Transcription initiated at Promoter upstream or downstream of Regulatory elements Concept map of transcription Examples of results from the scientific teaching approach Item Difficulty Index (P) P values (mean fraction correct answers) on each of the 25 GCA questions, pre- and post-tests, grouped by learning goal LG2 LG1 LG3 LG4 LG5 LG7 LG9 LG6 LG8 Question number n = 607 students Pre-test Post-test increment Smith, MK, Wood, WB, Knight, JK (2008) The Genetics Concept Assessment: a New Concept Inventory for Gauging Student Understanding of Genetics. CBE-Life Sci. Educ. 7: 422-430. Number of students Comparison of student normalized learning gains in traditional and interactive-engagement courses traditional interactive interactive % normalized learning gain Developmental biology,a required course for majors, ~70 junior and senior undergraduates, taught in Fall '03, Spr. 04,and Spr. 05. From JK Knight and WB Wood. Teaching more by lecturing less. Cell Biol Educ 4: 298-310 (2005). Second story:evidence for the value of group work Why does peer discussion improve student performance on in-class concept questions? The story of Prof. Tin Tin Su Question: Do students learn during the discussion, or are they simply influenced by their knowledgeable peers to choose the right answer? Experiment using isomorphic questions, Q1 and Q2: Q1 Students vote individually, correct answer and distribution not revealed. Peer discussion Q1ad Students re-vote, correct answer and distribution still not revealed. Smith MK, Wood WB, et al. (2009). Why peer discussion improves student performance on in-class concept questions. Science 323: 122-124. Q2 Isomorphic question: students vote individually, then correct answers and distributions revealed. Percent Correct Mean individual improvement from Q1 to Q2 for 16 isomorphic question pairs 100 90 80 70 60 50 40 30 20 10 0 Q1 Q1ad Q2 Mean Q2 score is significantly higher than mean Q1 score (16% ± 1%SE) Data from one of the Colorado majors genetics courses, 350 students On average, students who corrected their initial response to Q1 after discussion did much better on Q2 than students who did not correct their initial response All Students Q1 52% correct 41% correct Q1ad Q2 48% incorrect 84% correct 77% correct 59% incorrect 23% 44% incorrect correct 56% incorrect Conclusion: Most students are learning from peer discussion But how?? Transmissionist view: the stronger students explain the correct reasoning to the weaker students, who therefore now understand it (Mazur). Constructivist view: in the process of actively discussing and defending different points of view, students arrive at a correct understanding by themselves. Percent correct Mean individual improvement from Q1 to Q2 for question pairs of different difficulty 100 90 80 70 60 50 40 30 20 10 0 NG = 50% Q1 NG = 36% NG = 47% Q1ad Q2 Easy Medium Difficult (5 questions) (7 questions) (4 questions) NG: normalized gain from Q1 to Q2. Chi-square analysis on responses to each of the four difficult question pairs Model: Q1-correct students are randomly distributed among the participating groups. All students in these non-naïve groups, and only these students, answer Q2 correctly. Observed Predicted Observed Total correct on Q1 correct on Q2 24 (12%) 64 102 203 33.3 <0.01 44 (16%) 114 147 277 15.9 <0.01 50 (18%) 122 141 275 5.1 =0.02 52 (20%) 125 185 258 56.3 <0.01 correct students on Q2 participating χ2 p Conclusion: Most students are learning from peer discussion But how?? Transmissionist view: the stronger students explain the correct reasoning to the weaker students, who therefore now understand it (Mazur). Constructivist view: in the process of actively discussing and defending different points of view, students arrive at a correct understanding by themselves. Student surveys support the constructivist explanation Survey question (n=328 responding): When I discuss clicker questions with my neighbors, having someone in the group who knows the correct answer is necessary in order to make the discussion productive (agree/disagree). 47% of students disagreed. Student surveys support the constructivist explanation Comments from these students included: "Often when talking through the questions the group can figure out the questions without originally knowing the answer, and the answer almost sticks better that way because we talked through it instead of just hearing the answer." "Discussion is productive when people do not know the answers because you explore all the options and eliminate the ones you know can't be correct." Prof. Tin Tin Su . . . was senior author on the first classroom research paper to be published as a Report in Science: MK Smith, WB Wood, JK Knight, W Adams, C Wieman, and TT Su, Why peer discussion improves student performance on in-class concept questions. Science 323: 122-124 (2009). has changed her attitude toward teaching: "After teaching the same course for two years in a row, I always used to get bored with it. Now I can't wait for next fall, because there's another experiment I want to do!" is lead PI on a pending CCLI grant application to NSF, proposing to study the effects of active learning activities on longer term retention of key concepts in genetics. Acknowledgements: colleagues in MCD Biology Jennifer Knight, Ph.D. - SEI Coordinator Jia Shi - Science Teaching Fellow Michelle Smith - Science Teaching Fellow Twelve participating faculty members The University of Colorado Science Education Initiative http://www.colorado.edu/sei/