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The Molecular Genetics Learning Progressions: Revisions and Refinements Based on Empirical Estingt in Three 10Th Grade Classrooms Wright State University CORE Scholar Browse all Theses and Dissertations Theses and Dissertations 2013 The Molecular Genetics Learning Progressions: Revisions and Refinements Based on Empirical estingT in Three 10th Grade Classrooms Amber Nicole Todd Wright State University Follow this and additional works at: https://corescholar.libraries.wright.edu/etd_all Part of the Biomedical Engineering and Bioengineering Commons Repository Citation Todd, Amber Nicole, "The Molecular Genetics Learning Progressions: Revisions and Refinements Based on Empirical Testing in Three 10th Grade Classrooms" (2013). Browse all Theses and Dissertations. 1161. https://corescholar.libraries.wright.edu/etd_all/1161 This Dissertation is brought to you for free and open access by the Theses and Dissertations at CORE Scholar. It has been accepted for inclusion in Browse all Theses and Dissertations by an authorized administrator of CORE Scholar. For more information, please contact [email protected]. THE MOLECULAR GENETICS LEARNING PROGRESSIONS: REVISIONS AND REFINEMENTS BASED ON EMPIRICAL TESTING IN THREE 10TH GRADE CLASSROOMS A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy By AMBER NICOLE TODD A.S., Cottey College, 2003 B.A., Mount Holyoke College, 2005 __________________________________________ 2013 Wright State University COPYRIGHT BY AMBER NICOLE TODD 2013 WRIGHT STATE UNIVERSITY GRADUATE SCHOOL October 8, 2013 I HEREBY RECOMMEND THAT THE DISSERTATION PREPARED UNDER MY SUPERVISION BY Amber Nicole Todd ENTITLED The Molecular Genetics Learning Progressions: Revisions and Refinements Based on Empirical Testing in Three 10th Grade Classrooms BE ACCEPTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF Doctor of Philosophy. ! ___________________________ ! Lisa Kenyon, Ed.D. ! Dissertation Director ! ___________________________ ! Mill Miller, Ph.D. ! Director, Biomedical Sciences ! Ph.D. Program ! ___________________________ ! R. William Ayres, Ph.D. ! Interim Dean, Graduate School Committee on Final Examination ___________________________ ! Lisa Kenyon, Ed.D. ___________________________ ! Steven Berberich, Ph.D. ___________________________ ! Madhavi Kadakia, Ph.D. ___________________________ ! James Tomlin, Ed.D. ___________________________ ! Suzanne Franco, Ed.D. Abstract Todd, Amber Nicole. Ph.D., Biomedical Sciences Ph.D. program, Wright State University, 2013. The Molecular Genetics Learning Progressions: Revisions and Refinements Based on Empirical Testing in Three 10th Grade Classrooms. ! In the past few decades, there has been a large push for increasing scientific literacy (AAAS, 1989; AAAS, 1993; Achieve, 2013; NRC, 1996; NRC, 2012), especially in areas that are rapidly advancing, like molecular genetics. Much research has been done on student understandings of molecular genetics and the consensus is that the concepts are difficult both to learn and teach (Fisher, 1992; Horwitz, 1996; Kindfield, 1992; Lewis & Kattmann, 2004; Marbach-Ad & Stavy, 2000; Stewart et al., 2005; Venville & Treagust, 1998; etc.). Two learning progressions in molecular genetics have been produced (Duncan et al., 2009; Roseman et al. 2006), but both progressions are hypothetical as neither have been fully empirically tested. This study filled several gaps in molecular genetics research such as empirically testing the molecular genetics learning progressions in three 10th grade classroom contexts in different schools, determining the impact of curricular intervention units targeted to certain constructs of one of the progressions, and revising and refining the progressions based on empirical data. ! The data collected show that 10th grade students fall on the extremely low levels of the progression prior to instruction and progress through the defined levels of the Duncan et al. (2009) progression for each construct. Students hold several lower and intermediate ideas that were added to the progression as new levels in each construct. It iv was difficult to quantify the impact of the intervention units with quantitative data, but qualitative data suggest that certain ideas emphasized in the units such as a gene, protein, cell, trait scaffold and several specific examples of protein structures and functions were useful for students to understand ideas in molecular genetics. Additionally, two of the constructs of the Duncan et al. (2009) progression were divided into two new constructs each, and an entirely new construct was added to combine the Duncan et al. (2009) and Roseman et al. (2006) progressions. This is the first study to empirically test, revise, and refine all constructs of the Duncan et al. (2009) molecular genetics learning progression and to combine the Duncan and Roseman progressions into a single learning progression. v Table of Contents Page I. Introduction and Purpose!.................................................................................................1 ! Scientific Literacy!....................................................................................................1 ! Literacy in Molecular Genetics!................................................................................4 ! Learning Progressions!............................................................................................11 ! Revision and Refinement of Learning Progressions Based on ! Empirical Data!...........................................................................................15 ! The Molecular Genetics Learning Progressions!....................................................18 ! Purpose for Study...................................................................................................! 27 II. Methods!........................................................................................................................32 ! Study Context.........................................................................................................! 32 ! Intervention Units!..................................................................................................36 ! Data Collected........................................................................................................! 39 ! Theoretical Framework!..........................................................................................42 ! Development of Coding Schemes..........................................................................! 43 ! Data Analysis!.........................................................................................................54 ! Rubric to Learning Progression Revision and Refinement!....................................64 ! Statistical Analyses!................................................................................................65 ! Reliability...............................................................................................................! 67 ! Trustworthiness and Observer Effects!...................................................................67 vi ! Confidentiality and Risk Assessment!.....................................................................70 ! Institutional Review Board Approval.....................................................................! 72 III. Results.........................................................................................................................! 73 ! Empirically Testing and Revising the Molecular Genetics ! Learning Progressions................................................................................! 73 ! Construct A.................................................................................................! 74 ! Construct B!................................................................................................80 ! Construct C!................................................................................................86 ! Construct D!................................................................................................96 ! Construct E...............................................................................................! 102 ! Construct F...............................................................................................! 108 ! Construct G!..............................................................................................114 ! G1!.................................................................................................119 ! G2.................................................................................................! 124 ! Construct H!..............................................................................................127 ! Combining the Duncan et al. (2009) and ! Roseman et al. (2006) Progressions.............................................! 133 ! Impact of Intervention Units!................................................................................139 ! Protein Structure and Function!................................................................143 ! Gene, Protein, Cell, Trait Scaffold!...........................................................145 IV. Discussion!.................................................................................................................152 ! Empirically Testing and Revising the Molecular Genetics ! Learning Progressions..............................................................................! 152 vii ! Impact of Intervention Units!................................................................................159 V. Conclusion!..................................................................................................................170
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