Introduction

1. Student Reasoning Related to Matter and Energy Flow through Ecosystems: Lessons from Diagnostic Question Clusters Laurel Hartley1, Charles W. Anderson2, Brook Wilke2, Jonathon Schramm2, Charlene D’Avanzo3, Barbara Abraham4, Amy Arnett5, Alan Dickman6, Heather Griscom7, April Cordero Maskiewicz8, Chris Picone9 1University of Colorado Denver, 2Michigan State University, 3Hampshire College, 4Hampton University, 5Unity College, 6University of Oregon, 7James Madison University, 8Point Loma Nazarene University, 9Fitchburg State College Introduction Results • We investigated college students’ ability to trace matter and energy through processes that generate, transform and oxidize organic carbon at multiple scales. • Our work focuses on college student understanding of • Principles: Conservation of Matter and Energy • Processes: Generation, Transformation, and Oxidation of Organic carbon • Scale: Atomic-molecular, Cellular, Organismal, Ecosystem • Carbon-transforming processes are a prominent part of college-level biology curricula, but ideas are typically presented in disconnected ways. We believe that teaching students to explicitly and continuously apply the principles of conservation of matter and energy can lead to a deeper understanding of processes across multiple scales. • Most college student answers were a hybrid of scientific reasoning and informal accounts (Fig. 3). • Students demonstrated similar types of reasoning, both correct and incorrect, across the range of institutions. • Despite the fact that the type & frequency of active instructional interventions used by participating faculty varied, we observed learning gains pre- and post-instruction (Fig. 3). • Our results both corroborate patterns in student thinking identified in previous studies and lead to further hypotheses about student reasoning (Table 1). • We believe the pathway to scientific literacy requires students to learn to replace their informal reasoning and discourse with principled reasoning and discourse (Fig. 1). • Objectives: • Look for patterns in student reasoning related to principles, processes, and scales and generate hypotheses for further research. • Examine the effects of instruction on student understanding of carbon-related processes. Fig. 3. Proportions of students responding with various reasoning strategies before and after instruction. We classified each of the 42 questions according to the principle, process, and scale it addressed and compared all pre-test responses to all post-test responses in each given category. ‘No Data’ primarily means that a student either skipped the question or answered “I don’t know.” A informal explanation describes individuals, different at all scales, with different abilities/ purposes that create seemingly complex, unconnected results A scientific explanation uses simple principles, the same at all scales, governing matter and energy transformations Fig. 1. Contrasting account frameworks for reasoning about ecological processes. Methods • We developed diagnostic question clusters (DQCs) to investigate college students’ reasoning about the carbon cycle. DQCs included 7-10 multiple-choice, true/false and short-answer questions about single processes (e.g. respiration) and multiple processes (e.g. respiration and photosynthesis) posed at scales from molecular to ecosystem. • Faculty from 12 institutions (research universities, liberal arts colleges, community colleges) administered 4 DQCs, two focused on carbon cycling and two on energy flow, to 440 students in biology and ecology courses. One carbon and one energy DQC were used as pre- tests. Some form of inquiry-based instruction on the topics followed, with details of implementation at the discretion of the faculty. All four DQCs were then administered as post-tests, allowing analysis of differences among students both pre- and post-instruction, as well as between institutions, course types, and pedagogical approaches. • For further details about the DQCs and • particular items, please see our web site at: http://demos.patrickgmj.net/griffithdemo/ • At one university, interviews were conducted • to further explore student responses to written questions. Table 1. A selection of results for each principle from both overall written scores and individual assessments. The last column indicates the type of questions for further study that are emerging from this dataset. Conclusion this “hidden curriculum” for faculty, DQCs can be an effective tool on which to base further instructional interventions. Our results also show that it is difficult for most students to replace their informal reasoning with principled, scientific reasoning. Despite the fact that the principles of matter and energy conservation across multiple scales are fundamental to understanding biology, and particularly ecology, this research indicates that students are not as well-grounded in those principles as faculty often assume. By helping to diagnose Fig. 2. Description of DQC development process. This research is supported in part by a grant from the National Science Foundation: Diagnostic Question Clusters to Improve Student Reasoning and Understanding in General Biology Courses (NSF 0736943). Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.