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What is conceptual learning in chemistry and why should we promote it?.
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What is conceptual learning in chemistryand why should we promote it? David Yaron+, Michael Karabinos+, Jodi Davenport*, Jordi Cuadros+Department of Chemistry+ and Psychology*, Carnegie Mellon UniversityGaea Leinhardt, Jim Greeno, Karen EvansLearning Research and Development Center, University of PittsburghLaura Bartolo+, John Portman*Department of Information Science+ and Biology*, Kent State UniversityW. Craig Carter, and Donald SadowayDepartment of Materials Science, MIT
NSDL ChemCollective ChemDL MatDL Digital Library and Projects Overview Materials for Introductory chemistry Virtual labs Scenario based learning Tutorials Can a digital library provide a community space for promoting conceptual learning in chemistry? www.chemcollective.org Chem Ed DL Portal for all of chemistry Collaboration between ACS and J. Chem. Ed. www.chemeddl.org OLI Full online courses www.cmu.edu/oli PSLC Fundamental studies to advance the theory of learning www.learnlab.org Pittsburgh Science of Learning Center PSLC Open Learning Initiative OLI
ChemCollective as a Digital Library ChemCollective LearningTechnologist LearningScientists Educators Configurable virtual lab Tools for creating explanations and assessments Tools for data collection Activity and curriculum creation Feedback on classroom use Domain analysis Learning assessment
What is conceptual learning? • Physics’ Force Concept Inventory • Mathematical problem solving does not necessarily lead to ability to answer qualitative questions • Students learn what they practice. • Physics’ answer to “What is conceptual learning?” • Non-conceptual instruction students struggle with hard problems • Conceptual instruction Couple mathematical problem solving with qualitative questions
Conceptual learning • Being systematic about the goals of instruction and aligning the instruction to these goals • Four projects related to conceptual learning • Virtual lab • What is needed for scientific literacy? • Teaching chemical equilibrium • Molecular science across disciplines
Virtual laboratory • Goal: Connecting mathematics to authentic chemistry • Approach: Problem solving that involves experimental design and data analysis • Virtual Lab: Ability to “see” inside a solution removes one level of indirection in chemical problem solving
Classroom uses • In a computer lab • As take-home work • Pre- and post-labs • Lab make-ups • Supplement to in-class demonstrations • Current topic list • Molarity - Stoichiometry • Quantitative analysis - Chemical equilibrium • Solubility - Thermochemistry • Acids and bases • Problem types • Predict and check • Virtual experiment • Labs designed to be similar to common physical labs • Puzzle problems (open-ended and inquiry based experiments)
Virtual lab use • Replacing textbook-style problems with experimental design and data analysis problems • Breaks shallow “means-ends” problem solving strategy • 4 sections of 30-45 students working alone; 4-5 instructors/observers • The Virtual Lab format requires students to go beyond matching words to equations • Typical textbook problem • “When 10ml of 1M A was mixed with 10ml of 1M B, the temperature went up by 10 degrees. What is the heat of the reaction between A and B?” • Virtual Lab problem • “Construct an experiment to measure the heat of reaction between A and B?”
Virtual lab use “The virtual lab contains 1M solutions of A, B, C, and D. Construct experiments to determine the reaction between these reagents” 100 mL 1 M A + 100 mL 1 M C 0.25 M A + 0.25 M B + 0.25 M D • 50 % of students put A as reactant and product A + C A + B + D • Actual reaction A + 2 C B + D
Virtual lab use “The virtual lab contains 1M solutions of A, B, C, and D. Construct experiments to determine the reaction between these reagents” 100 mL 1 M A + 100 mL 1 M C 0.25 M A + 0.25 M B + 0.25 M D • Find stoichiometry through titration • Slowly add 1M A to 100 ml of C until all the C is consumed • 50 mL of A leads to 1:2 ratio of A to C in the reaction A + 2 C
Virtual lab use “The virtual lab contains 1M solutions of A, B, C, and D. Construct experiments to determine the reaction between these reagents” Single step solution • Mix equal volumes of 1M A, 1M B, 1M C, and 1M A B C D Initial 0.25 0.25 0.25 0.25 Change -0.125 +0.125 -0.25 +0.125 Final 0.125 0.375 0 0.375 A + 2 C B + D
Assessment within a large lecture course • Study at Carnegie Mellon • Second semester intro course, 150 students • Information used • Pretest • 9 homework activities (virtual labs with templated feedback) • 3 hour exams • 2 pop exams (practice exam given 5 days before hour exam) • Final exam
Regression and structural equation model • Linear regression accounts for 48% of the variance in the final grades • Influence of homework accounts for half of the model predictions • Structural equation model supports conclusions drawn from the regression
Text-only Mean=65 Multimedia Mean=77 Assessment within OLI online stoichiometry module • Study design • Treatment (20): Online course including a scenario, tutors and virtual lab homework • Control (20): Paper and pencil, worked examples and practice • Assessment was traditional problem solving of quantitative stoichiometry problems, and some qualitative questions Virtual Lab use was positively correlated with better performance.
Conceptual learning in chemistry: What is it? • Virtual laboratory • Connecting mathematics to authentic chemistry • What is needed for scientific literacy? • Teaching chemical equilibrium • Molecular science across disciplines
Conceptual learning in chemistry: What is it? • Virtual laboratory • Connecting mathematics to authentic chemistry • What is needed for scientific literacy? • Teaching chemical equilibrium • Molecular science across disciplines
Traditional high school course structure • CA state standards • Standard 1 Atomic and Molecular Structure • Standard 2 Chemical Bonds • Standard 3 Conservation of Matter and Stoichiometry • Standard 4 Gases and Their Properties • Standard 5 Acids and Bases • Standard 6 Solutions • Standard 7 Chemical Thermodynamics • Standard 8 Reaction Rates • Standard 9 Chemical Equilibrium • Standard 10 Organic Chemistry and Biochemistry • Standard 11 Nuclear Processes • Current chemistry AP exam guides are similarly structured around chemistry topic list
Domain analysis for chemical literacy • Evidence of the domain as practiced • Nobel prizes for past 50 years (1952-2002) • NY Times Science Times for 2002 (54 reports) • Scientific American News Bites for 2002 (32 reports) • Evidence of the domain as taught • CA state content standards • Best selling textbooks
EXPLAIN ANALYZE SYNTHESIZE Hypothesis Generation Goal(What do you want to know?) Functional Motifs Hypothesis Testing Process(How to determine What you have) Structural Motifs Assembly Motifs TOOLBOX Representational Systems Quantification Systems Domain map
Full domain map Evans, Karabinos, Leinhardt & Yaron, J. Chem. Ed. (2006)
Results of text analysis Synthesize Analyze Explain Toolbox Chem in the World Chem in Textbooks
Scenarios: Examples • Mixed reception (molecular weight, stoichiometry) • Cyanine dyes binding to DNA (equilibrium, Beer’s law) • Meals read-to-eat (thermochemistry) • Mission to mars (redox, thermochemistry) • Arsenic poisoning of wells in Bangladesh (stoichiometry, titration, analytical spectroscopy) • Ozone destruction (kinetics)
Conceptual learning in chemistry: What is it? • Virtual laboratory • Connecting mathematics to authentic chemistry • What is needed for scientific literacy? • Replacing skills focus with knowledge of what chemists do • Teaching chemical equilibrium • Molecular science across disciplines
Conceptual learning in chemistry: What is it? • Virtual laboratory • Connecting mathematics to authentic chemistry • What is needed for scientific literacy? • Replacing skills focus with knowledge of what chemists do • Teaching chemical equilibrium • Molecular science across disciplines
Chemical equilibrium • Goal: Discovery why this topic is so difficult to learn, and try to fix it • Approach: • Domain analysis • Student talk alouds on traditional problems • Discovered “implicit knowledge” that could be made explicit in the instruction
Chemical equilibrium • Goal: Discovery why this topic is so difficult to learn, and try to fix it • Approach: • Domain analysis 1. Utility of the knowledge 2. Detailed structure of the knowledge 3. Psychological aspects of the knowledge • Student talk alouds on traditional problems • Discovered “implicit knowledge” that could be made explicit in the instruction
Chemical equilibrium / Acid-base chemistry 1) Utility of the knowledge • How is this knowledge used in organic chemistry and molecular biology • Compare pH to pKa to determine ionization state • Buffers used to control pH (qualitative not quantitative) • Titration as an analytical technique • Current instruction 1: Almost a footnote (in the pH indicators section) 2-3: Coverage may not be sufficiently qualitative
Chemical equilibrium / Acid-base chemistry 2) Detailed structure of the knowledge • Need to be flexible with “progress of reaction” • General strategy (majority/minority species strategy) 3) Psychological aspects of the knowledge • LeChatlier (especially with addition/removal of a species) is most retained concept • Broad confusion regarding “progress of reaction” • Q (current state) vs. K (state towards which system tends) • Meaning of “initial” vs. “equilibrium” state
What can we build on? • LeChatlier’s principle plays role of “prior knowledge” • Human respiration is scenario to which to attach “initial” vs. “equilibrium” state • Blood entering lungs and muscles experiences a new initial state • Blood leaving lungs and muscles has reached a new equilibrium state
Progress of Reaction • Based on expert/novice protocol study 2NO2 N2O4
Majority / Minority Problem Solving Strategy • Old instruction • “Small x approximation” • Highly mathematical • New instruction • Majority/minority species strategy • Couples the problem solving steps to qualitative reasoning
Old Instruction Small x approximation
New Instruction Step 1:Push strong reactions to completion(identify majority species) Step 2:Use K=Q to find [ ]’s of minority species
Results • Coordination of core concepts with problem solving procedures led to large improvement in problem solving performance.
Majority vs. minority species • A general strategy • Find all strong reactions (K>>1) • Acid base: OH- + H+ ; HA + OH- and A- + H+ • Solubility: M+ + X- and M+ + L • Thought experiment: Assume large K’s are infinite and do a limiting reagent calculation • All species that do not go to zero, are majority species and you now know their concentration • Determine minority species, via equilibrium expressions (K=Q)
Conceptual learning in chemistry: What is it? • Virtual laboratory • Connecting mathematics to authentic chemistry • What is needed for scientific literacy? • Replacing skills focus with knowledge of what chemists do • Teaching chemical equilibrium • Connecting problem solving procedures to chemical concepts/mental models • Molecular science across disciplines
Conceptual learning in chemistry: What is it? • Virtual laboratory • Connecting mathematics to authentic chemistry • What is needed for scientific literacy? • Replacing skills focus with knowledge of what chemists do • Teaching chemical equilibrium • Connecting problem solving procedures to chemical concepts/mental models • Molecular science across disciplines
Conceptual frameworks that cross disciplines • Scope is molecular science • How molecular structure and motion lead to emergent macroscopic properties • The synthesis/engineering of structures with desirable properties • Build materials for discipline-specific courses, but that use a common core set of materials to show interdisciplinary connections • Experts from multiple domains (chemistry, materials science, biophysics) met to identify concepts/frameworks that are • Central to their domain • Have strong leverage • Are difficult to teach/learn
Outcome of the Design Process • Reaction paths and energy landscapes • Used to describe, for example, • Organic chemistry reactions • Diffusion on surfaces • Protein folding/unfolding
Development process • Analyze content with experts, novices and psychologists • Sequential focus on aspects of the diagram • What is Q? • What is temperature? • Energy vs. free energy
Other conceptual frameworks of molecular science • Reaction paths and energy landscapes • Molecular forces • e.g. Structure formation at different temperatures • Economies of exchange • Heat, proton (acid/base) and electron (redox) exchange • How natural and designed systems promote one chemical process over another • e.g. Kinetic vs. thermodynamic control
Conceptual learning in chemistry: What is it? • Virtual laboratory • Connecting mathematics to authentic chemistry • What is needed for scientific literacy? • Replacing skills focus with knowledge of what chemists do • Teaching chemical equilibrium • Connecting problem solving procedures to chemical concepts/mental model • Molecular science across disciplines • Conceptual frameworks that have broad utility
Digital library assessment • Web logs • Monitoring the pathway from seeing to contributing • Target audience: 9000 college and 100,000 high school instructors • See the collection: 7000 • Use the collection: 200 • Contribute to the collection: 62 • 11 have contributed activities (56 activities) • 11 have contributed translations (11 languages, 70 activities) • 40 have given feedback, 13 volunteered for learning studies
Closing comments • Can digital libraries serve as community spaces for promoting conceptual teaching and learning of chemistry? • Virtual lab does get reused and repurposed • Homework tool • Many instructors find the approach compelling • Chemical equilibrium and cross-disciplinary materials • Too soon to tell • Shifting high school chemistry from skills to literacy • No progress yet
Thanks To • Erin Fried • Jason Chalecki • Greg Hamlin • Brendt Thomas • Stephen Ulrich • Jason McKesson • Aaron Rockoff • Jon Sung • Jean Vettel • Rohith Ashok • Joshua Horan LRDC, University of Pittsburgh • Gaea Leinhardt • Jim Greeno • Karen Evans • Baohui Zhang Carnegie Mellon • Michael Karabinos • Jodi Davenport • Donovan Lange • D. Jeff Milton • Jordi Cuadros • Rea Freeland • Emma Rehm • William McCue • David H. Dennis • Tim Palucka • Jef Guarent • Amani Ahmed • Giancarlo Dozzi • Katie Chang Funding • NSF: CCLI, NSDL, SLC • William and Flora Hewlett Foundation • Howard Hughes Medical Institute • Dreyfus Foundation