The Problem Since many geologic processes are unobservable due to the inaccessible scale of geologic time and the fact that many processes occur deep within the Earth, student conceptions of geologic phenomena are influenced by events other than what is readily directly observable. UW Colleges freshman / sophomore students often begin geoscience courses with their own conceptions of how the earth system works. Some of these ideas include alternative concepts or misunderstandings of scientific information which can affect their abilities to remember and acquire new knowledge. This prior understanding often is not the result of formal science instruction but instead may include constructing ideas gathered from popular culture (i.e. TV, science fiction movies and books), misapplication of earlier learned scientific facts gleaned from prior courses, and sometimes misinformation and myths. Students' alternative conceptions and personal understanding of the physical world around them can impact the way in which they learn and retain the formal geoscience instruction that they are exposed to. Summer 2007

Divisions of the Earth's Interior Methodologies & Types of Evidence of Student Learning Gathered Students were instructed to produce hand drawn (paper / pencil) concept sketches related to plate tectonics concepts. Some sketches were drawn in class while at other times students constructed them outside of class as homework assignments. When finished with their concept sketches, students exchanged their sketches with a classmate who critiqued the model / sketch. The sketches were then returned to the original student who then read the critique and drew a revised model. In the revision the students reflected on their revisions by addressing a new set of questions. Students went through a series of 3 concept sketch cycles: 1) after the introductory lecture on plate tectonics 2) after completing the plate tectonics unit of the course 3) at the end of the semester, approximately 2 ½ months after any formal class discussion of the topic. Results of these activities were evaluated during the spring 2008 semester. (See link below for an example of a concept sketch assignment) As a second method of assessment, students completed a concept survey based on a subgroup of questions taken from the "Geoscience Concept Inventory" developed by Julie Libarkin and Steve Anderson (see links below). This survey was administered as a pretest at the beginning of the semester and post test at the end of the semester. Fall 2007 Example of a concept sketch assignment Geoscience Concept Inventory created by Julie Libarkin & Steve Anderson Geoscience Concept Inventory webpage Subset of questions from the GCI This is the survey I used as a pre- and post-test assessment.

Project Summary The purpose of this project was to identify and characterize the different types of conceptual understanding and mental models held by UW Colleges introductory-level geoscience students about the inside of the earth and the causal and dynamic processes involved in plate tectonics. It is important that these previously held concepts are consistent with the ideas accepted by scientists in order to assimilate further concepts. The presence of erroneous previously held concepts may impede the understanding of earth science concepts. Through the use of student-generated annotated drawings (also known as concept sketches), I hope to help students recognize conflicting explanations for natural phenomena that they may have and to help them realize why some of their personal, sometimes long-held, beliefs about the earth system may in fact be misconceptions. Identifying the alternative conceptions students may hold will allow me to better create instruction materials that explicitly targets the alternative conceptions. ongoing

Helpful Resources & References Dahl, J., Anderson, S.W., and Libarkin, J., 2005; Digging into Earth science: Alternative conceptions held by K-12 teachers; Journal of Science Education, v. 12, p. 65-68. Delaughter, J.E., Stein, S., Stein, C.A., and Bain, K.R., 1998, Preconceptions abound among students in an introductory earth science course, EOS, v. 79, p.429-431. Duncan F. Sibley, 2005, Visual Abilities and Misconceptions about Plate Tectonics; Journal of Geoscience Education, v. 53, p. 471-477. Gobert, J.D., 2000, A typology of causal models for plate tectonics; Inferential power to understanding; International Journal of Science Education, v22 n9 p937-77. Gobert, J.D, 2005, The effects of different learning tasks on model-building in plate tectonics; diagramming versus explaining; Journal of Geoscience Education, vol.53, no.4, pp.444-455 Gobert, J. and Coleman, E.B., 1993, Using diagrammatic representations and causal explanations to investigate children's models of continental drift, Proceedings of the Society of Research in Child Development, March 25-28, New Orleans, LA. King, C. 2000. The Earth's Mantle Is Solid: Teachers' Misconceptions about the Earth and Plate Tectonics. School Science Review; v82 n298 p57-64. King, C., 2000, The Earth's Mantle Is Solid: Teachers' Misconceptions about the Earth and Plate Tectonics: School Science Review; v. 82, no. 298, p57-64. Philips, W., 1991, Earth Science Misconceptions: Science Teacher, v. 58, no. 2, p. 21-23. Libarkin, J.C., 2006, College Student Conceptions of Geological Phenomena and Their Importance in Classroom Instruction; Planet, v. 17, p. 6-9. Libarkin, J.C., and Anderson, S.W., 2006, The Geoscience Concept Inventory: Application of Rasch analysis to concept inventory development in higher education; Rasch Applications in Science Education, ed. X. Liu, JAM Publishers, in press Libarkin, J.C., Anderson, S.W., Dahl, J., Beilfuss, M., Boone, W., and Kurdziel, J.P., 2005a. Qualitative analysis of college students' ideas about the Earth: Interviews and open-ended questionnaires; Journal of Geoscience Education, v. 53, p. 17-26. Libarkin, J.C., and Anderson, S.W., 2005b, Assessment of Learning in Entry-Level Geoscience Courses: Results from the Geoscience Concept Inventory; Journal of Geoscience Education; v. 53. p. 394-401. Sibley, D.F., 2005, Visual Abilities and Misconceptions about Plate Tectonics; Journal of Geoscience Education, v. 53, no. 4, p. 471-477.

Results, Conclusions, & Implications During the Fall 2007 semester I gathered data in the form of a series of 3 student produced concept sketches, as well as results from a pre- and post-test geoscience concept survey. I informed my students I that would not look at or evaluate their work on this project until after the fall semester grades were determined. Concept Sketch Results As anticipated, it was found that students held a wide range of preconceptions about the dynamic physical nature of the earth. Unfortunately some of the misconceptions students held at the beginning of the course remained after completion of the course. In order to reveal what some of these alternative conceptions were, students constructed sketches of what they thought the interior of the earth looks like in cross section. Along with their sketches, students wrote an explanation of what they think happens inside the earth. (see an example of the assignment in the "methodology" section to the left) Students also were asked to finish the following two statements: "the movement in the crust of the earth is caused by....", and "rocks from the floor of the Atlantic Ocean test to be younger than rocks from the middle of the North American continent because...." Before students received an introductory lecture on the topic of plate tectonics, only 2 percent of the students correctly drew sketches of the earth's interior with spherical layers that were labeled using either compositional or physical state terms according to current scientifically accepted hypotheses and geophysical data. By the end of the semester 64 percent of students produced scientifically "accurately" drawn and labeled sketches of the earth's interior. Following the completion of the plate tectonics lectures, when asked to explain what is causing the movement of the crust, students responded with a wide variety of explanations and only 19 percent had responses that included convective heat flow from the underlying asthenosphere. 56 percent of students simply stated the cause of crustal movement was "plate tectonics", without any explanation. By the end of the semester, that over simplified response dropped to 33 percent. Also by the end of the semester, 50 percent of students in the study had acceptable "correct" scientific explanations for crustal movement. During the assessment cycle following completion of the unit on plate tectonics, when students completed the statement that rocks from the seafloor dated younger than those found on continental crust, 47 percent of students explained the observed phenomena by the continued creation of new ocean floor at seafloor spreading rifts and the rapid recycling of ocean floor into the mantle whereas when repeating the assignment at the end of the semester, only 37 percent of students responded this way. Alternative incorrect responses included: that seafloor rocks are younger because the seafloor is thinner; that continents move while ocean floor does not; and that ocean crust is thicker than continental crust and therefore oceanic crust erodes more slowly. Survey Results As a second method of assessment, students completed a concept survey based on a subgroup of questions taken from the "Geoscience Concept Inventory" developed by Julie Libarkin and Steve Anderson (see reference list). This survey was administered twice, once as a pretest at the beginning of the semester and again as a post test at the end of the semester. At the top of this panel is a comparison of the pre- & post-test survey scores of 17 introductory-level students enrolled in Glg 101: Physical Geology for the fall 2007 semester. Each data point represents an individual score. The solid line on the graph indicates no change between pre- and post-test scores. Points that fall below the line indicate a decrease from pre- to post-test score for an individual while points above the line indicate improvement in scores. (see link below for scores from pre- and post-tests) Conclusion As a result of these activities it is clear that students demonstrated exposure to plate tectonics ideas but that that they leave my classroom with incomplete understanding. Some students hold on tightly to alternative conceptions about natural phenomena and my having a better understanding of what those conceptions are will help me to create instruction that targets those alternative conceptions. I will continue to repeat the activities used in this investigation but with modifications. For example, when students were asked to draw their concept sketches as assignments outside of the classroom I found that some students simply tried to reproduce diagrams available to them from their course textbook with little thought about the explanations of these diagrams. In the future I will have students construct all of their sketches in class to hopefully better reveal students' personal beliefs and understands of the content. Spring 2008 pre & post-survey results Click here for a graphic comparison of pre- and post-test survey results

Career Relevance & Impact Being involved in the Wisconsin Teaching Fellows Program has helped me become a better educator. Through the many interactions with other UW instructors and the meaningful seminars and workshops offered through the OPID office I have accumulated additional "tools" in my teaching bag. Developing this SoTL project has given me additional tangible methods for checking the progress of my student's learning and has helped make my students' learning more visible both to them and to me. The WTF program has also helped me be aware of more resources that are available for SoTL projects. I am more apt now to increase the number of inovative teaching methods I try. Thank you WTF / WTS Program and the OPID office! Ongoing