Development and Validation of a Rubric for Diagnosing Students\u27 Experimental Design Knowledge and Difficulties

It is essential to teach students about experimental design, as this facilitates their deeper understanding of how most biological knowledge was generated and gives them tools to perform their own investigations. Despite the importance of this area, surprisingly little is known about what students actually learn from designing biological experiments. In this paper, we describe a rubric for experimental design (RED) that can be used to measure knowledge of and diagnose difficulties with experimental design. The development and validation of the RED was informed by a literature review and empirical analysis of undergraduate biology students’ responses to three published assessments. Five areas of difficulty with experimental design were identified: the variable properties of an experimental subject; the manipulated variables; measurement of outcomes; accounting for variability; and the scope of inference appropriate for experimental findings. Our findings revealed that some difficulties, documented some 50 yr ago, still exist among our undergraduate students, while others remain poorly investigated. The RED shows great promise for diagnosing students’ experimental design knowledge in lecture settings, laboratory courses, research internships, and course-based undergraduate research experiences. It also shows potential for guiding the development and selection of assessment and instructional activities that foster experimental design

A Vision for Change in Bioscience Education: Building on Knowledge from the Past

High quality undergraduate education is central to the success of all life scientists. Several major bioscience educational issues are the targets of much debate, research, funding, publications, and reports (e.g. Vision and Change). Surprisingly, these issues are considered by modern bioscience instructors as unresolved despite historical reports that claim the contrary. Here we illustrate with evidence how, more than 50 years ago, Sam Postlethwait successfully instituted strategies to address several issues in plant biology education with his audio-­‐tutorials. These strategies succeeded in individualizing instruction of students with diverse educational backgrounds in large classes, incorporating authentic and active learning, integrating lab and lecture to teach about research, developing science competencies, and advancing curriculum and faculty change informed by empirical data. We contend that modern educators could greatly benefit by building on the historical advancements of the past, to ensure they do not waste their efforts re-­‐ inventing the wheel

An Activity Aimed at Improving Student Explanations of Biological Mechanisms

This document is intended for use by instructors and their students. The activity contains steps to introduce students to the MACH model involving analyzing and discussing explanations about biological mechanisms. Initially, students read modified articles about biological mechanisms during class, although instructors may prefer to assign readings outside of class before the activity. During the activity, students are required to analyze the readings for evidence of research methods, analogies, context, and mechanisms. In so doing, students learn how to integrate the information pertaining to each of the MACH model components into a coherent explanation about their biological mechanism. After performing the above activities individually, students discuss findings in pairs, and then share their ideas with the class. After discussion, the instructor presents the MACH model. In our experience once the above activity has been successfully completed, students show strong evidence of competence in the writing of explanations about mechanisms. Details of the tetrahedral MACH model, and its related class activities, are freely available in the Purdue International Biology Education Research Group (PIBERG) ePubs collection. Together with the description of the activity, we have included advice on suggested topics, citations of suggested readings, and examples of typical student analyses of such readings. This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License

A Model of the Use of Evolutionary Trees (MUET) to Inform K-14 Biology Education

Evolutionary trees are powerful tools used in modern biological research, and also commonly used in textbooks and classroom instruction. Studies have shown that K-14 students have difficulties interpreting evolutionary trees. To improve student learning about this topic, it is essential to teach them how to understand and use trees like professional biologists. Unfortunately, few currently used teaching frameworks for evolution instruction are designed for this purpose. In this study we developed the Model of the Use of Evolutionary Trees (MUET), a conceptual model that characterizes how evolutionary trees were used by professional biologists as represented in their research publications. The development of the MUET was guided by the Concept-Reasoning-Mode of representation (CRM) model as well as a “model of modeling” framework. The MUET was then used to review instructional and assessment material for K-14 classrooms. Future studies with the MUET may inform the development of teaching materials for K-14 classrooms aimed at improving students’ understanding of and learning about evolutionary trees

Exploring the MACH Model’s Potential as a Metacognitive Tool to Help Undergraduate Students Monitor Their Explanations of Biological Mechanisms

When undergraduate biology students learn to explain biological mechanisms, they face many challenges and may overestimate their understanding of living systems. Previously, we developed the MACH model of four components used by expert biologists to explain mechanisms: Methods, Analogies, Context, and How. This study explores the implementation of the model in an undergraduate biology classroom as an educational tool to address some of the known challenges. To find out how well students’ written explanations represent components of the MACH model before and after they were taught about it and why students think the MACH model was useful, we conducted an exploratory multiple case study with four interview participants. We characterize how two students explained biological mechanisms before and after a teaching intervention that used the MACH components. Inductive analysis of written explanations and interviews showed that MACH acted as an effective metacognitive tool for all four students by helping them to monitor their understanding, communicate explanations, and identify explanatory gaps. Further research, though, is needed to more fully substantiate the general usefulness of MACH for promoting students’ metacognition about their understanding of biological mechanisms

A Tetrahedral Version of the MACH Model for Explaining Biological Mechanisms

This document is intended for both instructors and students. Modified from the original MACH model this version, once cut and folded, creates a tetrahedral model that can conveniently be used as a teaching and learning tool to inform and guide students on how to write expert quality explanations of biological mechanisms. Each vertex of the tetrahedron represents a component of the model namely, Methods, Analogy, Context, and How. For a coherent and complete explanation about molecular mechanisms, it is important to integrate information pertaining to all four components of the model. The tetrahedral MACH model has been tested in both undergraduate biology and biochemistry courses and is recommended for use by both practitioners and students in the life sciences. Details of its use as a classroom activity can be found in the Purdue International Biology Education Research Group (PIBERG) ePubs collection. This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License

A Model of How Different Biology Experts Explain Molecular and Cellular Mechanisms

Constructing explanations is an essential skill for all science learners. The goal of this project was to model the key components of expert explanation of molecular and cellular mechanisms. As such, we asked: What is an appropriate model of the components of explanation used by biology experts to explain molecular and cellular mechanisms? Do explanations made by experts from different biology subdisciplines at a university support the validity of this model? Guided by the modeling framework of R. S. Justi and J. K. Gilbert, the validity of an initial model was tested by asking seven biologists to explain a molecular mechanism of their choice. Data were collected from interviews, artifacts, and drawings, and then subjected to thematic analysis. We found that biologists explained the specific activities and organization of entities of the mechanism. In addition, they contextualized explanations according to their biological and social significance; integrated explanations with methods, instruments, and measurements; and used analogies and narrated stories. The derived methods, analogies, context, and how themes informed the development of our final MACH model of mechanistic explanations. Future research will test the potential of the MACH model as a guiding framework for instruction to enhance the quality of student explanations

Development of a Game‐Based‐Learning App for Exposing Students to Chemistry and Life Science as a Research Endeavor

We have developed a gamified Virtual Learning Environment (VLE), called 3DClass, to deliver homework to chemistry and life science students through a user-­‐friendly and enjoyable interface. Homework from four courses was delivered using the 3DClass, a computer app that acts as an interface between Moodle and the Apple Game Center. This App allows users to play while learning or to learn while playing. The results show that this App can be used in a flexible manner with designs that can be customized to courses with different characterisOcs, such as with online collaboraOon or face-­‐to-­‐face lectures, and for parOcipant numbers that vary for courses with 20 to 600 students. The design accommodates the delivery of quizzes, and 3DClass also allows students to compete with each other for achievements in the Apple Game Center. It can deliver video, images, and promote student interacOons using a forum. The Open Quizzes can be taken without being registered in any of the courses and anyone can download the 3DClass App without cost

Development of the Neuron Assessment for Measuring Biology Students’ Use of Experimental Design Concepts and Representations

Researchers, instructors, and funding bodies in biology education are unanimous about the importance of developing students’ competence in experimental design. Despite this, only limited measures are available for assessing such competence development, especially in the areas of molecular and cellular biology. Also, existing assessments do not measure how well students use standard symbolism to visualize biological experiments. We propose an assessment-design process that 1) provides background knowledge and questions for developers of new “experimentation assessments,” 2) elicits practices of representing experiments with conventional symbol systems, 3) determines how well the assessment reveals expert knowledge, and 4) determines how well the instrument exposes student knowledge and difficulties. To illustrate this process, we developed the Neuron Assessment and coded responses from a scientist and four undergraduate students using the Rubric for Experimental Design and the Concept-Reasoning Mode of representation (CRM) model. Some students demonstrated sound knowledge of concepts and representations. Other students demonstrated difficulty with depicting treatment and control group data or variability in experimental outcomes. Our process, which incorporates an authentic research situation that discriminates levels of visualization and experimentation abilities, shows potential for informing assessment design in other disciplines