Conceptual Elements: A Detailed Framework to Support and Assess Student Learning of Biology Core Concepts

INTRODUCTION

The Vision and Change in Undergraduate Biology Education: Call to Action report (American Association for the Advancement of Science, 2011) calls for undergraduate biology educators to develop students’ understanding of core concepts across biological scales and to develop students’ ability to synthesize information in ways that connect conceptual domains (National Research Council [NRC], 2009). The report recommends that biology educators structure undergraduate teaching around five core concepts, which we focus on here, and six core competencies. The Vision and Change core concepts (pathways and transformations of energy and matter [PTEM], information flow, storage and exchange [IFES], structure and function [SF], evolution [E], systems [S]) emerged from decades of effort within the biology education community to identify and define the overarching concepts essential for understanding biology (e.g., NRC, 2003; Klymkowsky, 2010; Scheiner, 2010; Quinn et al., 2011; for more, see Table 1 in Brownell et al., 2014). Though the five core concepts offer a comprehensive profile of biology, they are so broad that it can be challenging for biology educators to unpack their complexity in ways that allow them to be used to write learning objectives, design instructional materials, and develop aligned assessments.

To begin unpacking this complexity, Brownell and colleagues developed the BioCore Guide, which offers subdisciplinary interpretations of the Vision and Change core concepts (Brownell et al., 2014). The BioCore Guide outlines a few general overarching principles defining each core concept and defines several subconcepts within subdisciplinary fields and their generally associated biological scales. The Conceptual Elements (CE) Framework presented here provides a more detailed comprehensive list of overarching principles that can be used as a tool to make connections across subdisciplines and scales (Table 1), thus complementing the BioCore Guide’s exploration of each core concept within subdisciplines and scales. Overall, the elements in the CE Framework were developed to construct a comprehensive understanding of each core concept across all biological scales and subdisciplines. We recognize that the development of a framework that is broad enough to encompass learning outcomes for the breadth of biology yet unencumbered with details is an especially lofty challenge (Dirks and Knight, 2016). We offer the detailed CE Framework here as a tool to be field-tested and invite the community to partner with us to refine it (see Next Steps in Development).

The generality of our approach is intentional and meant to address the need to support novice learners in understanding the breadth of biology by providing a foundation for students to organize their knowledge. With the CE Framework, educators can generate isomorphic learning objectives that span biological phenomena and help students make connections across subdisciplines to better understand how biology is not simply a jumble of facts that they must memorize. Novice thinkers generate linear connections between distinct bits of knowledge, while expert thinkers generate a network of connections that facilitate knowledge retrieval and transfer of knowledge to novel situations (Ambrose et al., 2010; Smith et al., 2013). Therefore, it is ideal to provide novice learners with tools to practice complex knowledge organization. The CE Framework, which provides common conceptual components across biology, can be used to guide the development of instructional tools that have the potential to build connections across a curriculum and move students toward expert thinking.

In addition, the broad approach provides flexibility in application of the CE Framework to meet user goals. In general, we highlight three primary areas for application: 1) developing instructional materials to support student learning, 2) developing and aligning learning objectives and assessments, and 3) evaluating existing curricula; however, we think further application is possible and left to the imagination of the user. First, the CE Framework offers enough detail to guide the development of instructional materials that focus on teaching the complexity of the five core concepts. Second, the CE Framework can guide the development and alignment of learning objectives and assessments that measure student learning of the five core concepts. Third, the CE Framework can provide a metric for evaluating the depth and breadth of core concept coverage of existing course objectives, instructional materials, and assessments across a curriculum, since it transcends biological subdisciplines and scales. Overall, the CE Framework can guide curricular reform efforts by documenting, comparing, and tracking progress of student learning of the core concepts across courses in an undergraduate biology curriculum, from introductory to advanced level. In addition, for departments pursuing Partnership for Undergraduate Life Sciences Education (PULSE) accreditation, the CE Framework can be used to generate evidence for their PULSE rubric rankings (Aguirre et al., 2013).

Here, we describe the development and validation of the CE Framework, including local field-testing as part of two biology education research projects and a national review by experts from a variety of subdisciplines that evaluated the CE Framework for scientific accuracy and completeness (Figure 1).

DEVELOPMENT OF THE CE FRAMEWORK

Phase 1: Exploring the Literature to Generate a Preliminary Draft

To begin, we analyzed and integrated currently available resources designed to promote student conceptual understanding in biology. Specifically, we started with the principles of each core concept, as defined in the BioCore Guide (Brownell et al., 2014) and elaborated upon in the Essential Concepts for Biology (Dirks and Knight, 2016), and compared these with biological concepts presented in other available resources ranging from concept inventories to student misconceptions (Table 2). We gathered feedback from local biology experts with diverse subdisciplinary training and used a reductionist approach to identify key elements of each core concept that span biological scale and subdiscipline. We then wrote concise statements describing each conceptual element to produce a preliminary draft of the framework, which had a total of 33 conceptual elements (9-PTEM, 6-IFES, 4-SF, 9-E, 5-S). Each conceptual element for a single core concept represents one piece of a puzzle that must be interlaced with the other elements to construct a comprehensive understanding of that core concept.

Phase 2: Local Review and Field-Testing

We recruited 14 local faculty members and biology instructors with expertise across a variety of biological subdisciplines to review the preliminary draft of elements and provide detailed feedback. We simultaneously conducted local field-testing while iteratively refining the CE Framework based on local reviewer feedback gathered through an online survey, one-on-one meetings, and small focus groups. Each local reviewer independently reviewed the framework for scientific accuracy and completeness and was asked to provide feedback and suggestions in his or her area of expertise. Specifically, reviewers were asked to determine whether each list of elements was complete and, if not, to identify the missing elements. We also asked them to rate the scientific accuracy of the elements for each concept as low, medium, or high. If ratings of low or medium were given, reviewers were asked to explain the ratings and make suggestions for improvement.

Four to six local reviewers provided detailed feedback for each concept. At this stage of development, greater than or equal to 80% of the reviewers determined that the lists were complete for all concepts, except evolution (only 67% agreement; Figure 2). Scientific accuracy was deemed as “medium” or “high” for all of the conceptual elements for each core concept, with “high scientific accuracy“ ratings for each concept ranging from 50% to 83% (Figure 2). In addition, we asked these reviewers to provide biological examples from their areas of expertise that demonstrate individual conceptual elements. The examples were used 1) to validate whether the elements transcended biological subdisciplines and scales and 2) to refine the conceptual elements language so that it was general enough to be applied across subdisciplines.

To field-test the preliminary draft of the CE Framework for completeness and accuracy, we applied the framework in two biology education research projects that were focused on measuring student understanding of the Vision and Change core concepts. For each project, the CE Framework was used as a rubric to evaluate student-generated responses to open-ended questions. We evaluated the utility and completeness of the framework based on the robustness of the CE Framework to assess student understanding. The first project tested how well the CE Framework characterized the complexity of student responses when asked to explain what they knew about each core concept. The second project tested how well the CE Framework captured the complexity of student responses when asked to apply their knowledge of the core concepts to a specific biological phenomenon (manuscripts from these projects are in preparation). Overall, the CE Framework yielded systematic coding of student responses from multiple trained coders and allowed us to assess what students understood (or did not understand) about each concept.

However, some students’ responses in these field tests could not be coded using the CE Framework. For these responses, we evaluated whether they represented misconceptions, inaccurate conceptions, or an element that was missing from the framework. After careful review, we determined that all of the noncoded answers were either misconceptions or inaccurate conceptions, and not missing elements. This suggested that, although the preliminary draft of the CE Framework needed revision, it was complete. The relative ease with which the framework could be applied successfully in these two projects with very different study aims suggested that the CE Framework did indeed describe fundamental building blocks that could be broadly applied in biology. At the end of this phase of development, the CE Framework still had a total of 33 conceptual elements, but PTEM was reduced by one element and one element was added to SF (8-PTEM, 6-IFES, 5-SF, 9-E, 5-S).

Phase 3: National Review

We recruited 48 experts in the biological sciences from across the nation to review the revised draft of the CE Framework and provide specific feedback on each element through an online survey. Of the reviewers, 81% were faculty members, 11% instructors, 1% professional staff, and 7% postdoctoral trainees. The majority (69%) held positions at PhD-granting institutions, and the remaining reviewers were at institutions that granted master’s (15%) and bachelor’s (17%) degrees. Eighty-nine percent had taught an introductory undergraduate biology course, and 72% had taught an upper-division undergraduate biology course in the past 3 years. The breadth and emphasis of the reviewers’ areas of self-reported expertise is represented in Figure 3.

Reviewers were asked to rate each core concept and its list of elements for readiness for use by the biological sciences community (Figure 4). They were instructed to consider the scientific accuracy and completeness of the list of elements for each concept to determine their ratings. The vast majority of reviewers rated the revised draft as “ready” or “ready with minor revisions” for use by the community (PTEM: 96%; IFES: 94%; SF: 96%; E: 96%; S: 92%). Consequently, the final number of elements for only two of the core concepts changed as a result of the national review. PTEM was reduced from eight to seven elements, and IFES was reduced from six to five elements for a total of 31 elements in the final draft. However, for all core concepts, national reviewers made suggestions for minor changes in the language and suggestions to combine two elements into one or to divide a single element into two separate elements. We especially focused on suggestions from a few reviewers who rated the elements as needing major revisions, but all suggestions were used to generate the final framework. The specific suggestions for improvement provided by the national reviewers were compiled, analyzed, and incorporated into the final list of key elements presented in Table 1 as the CE Framework.

NEXT STEPS IN DEVELOPMENT

Further refinement of the CE Framework will require feedback through national field-testing with faculty across a breadth of subdisciplines and at various types of institutions. We invite those interested in participating in such a study to contact us.

USING THE CE FRAMEWORK

Our motivation for developing the CE Framework was driven by our desire to operationalize the defined Vision and Change core concepts across biological subdisciplines for students enrolled in introductory biology. Although our initial application of this framework in local field-testing focused on assessment of student learning, we envision that individual instructors, departments, and institutions could use the CE Framework in a variety of ways. These include but are not limited to 1) developing instructional materials to support student learning, 2) developing and aligning learning objectives and assessments, and 3) evaluating existing curricula.

Developing Instructional Materials to Support Student Learning

As our ability to investigate biological systems becomes more sophisticated and our understanding of biological phenomena advances, we must train future biologists with the skills needed to tackle complex, interconnected biological questions (NRC, 1999; President’s Council of Advisors on Science and Technology, 2012). We need to prepare students to transfer knowledge to new contexts, define complex problems in ways that can be investigated, and apply their problem-solving skills to real-world challenges (Woese, 2004; Goldenfeld and Woese 2007). Although most introductory biology instructors strive to engage students with higher-order thinking, a study by Momsen et al. (2010) showed that the majority of introductory biology courses rely on rote memorization. We propose that educators can use the CE Framework as an instructional tool in introductory biology and throughout a curriculum to help students identify, understand, and apply the core concepts as a means of promoting higher-order thinking.

One example of the way that the CE Framework could be used to foster conceptual thinking is to have students use it to guide identification of the core concepts and the specific key elements represented in a newly presented biological phenomenon. In Table 3, we present three biological phenomena and provide three conceptual elements that align with each phenomenon as an example of how this could work in the classroom. Students could be asked to generate an explanation of a biological phenomenon individually or as a group and then to use the CE Framework to identify all of the elements present in their descriptions. In this way, they will practice linking specific knowledge and facts about the phenomenon to the general principles represented in the elements.

Instructors might also ask students to use the conceptual elements to make connections with material that they have learned in other courses across a curriculum, thereby supporting integration of learning across subdisciplines and biological scales. In Table 4, we demonstrate how the conceptual elements provide a common infrastructure that can be used to connect examples of biological phenomena that are typically taught in different undergraduate biology courses, yet address the same conceptual elements. An exercise in which students are provided examples from a current and previous course and then asked to connect them using the CE Framework could be used to help students make connections between courses. Beyond individual courses, this type of exercise may be used in a capstone course, where examples relevant to a complex problem could be taken from different courses across a curriculum. Students could be asked to use the CE Framework to integrate and apply their knowledge of the various examples to investigate the complex problem, thereby creating expert-like networks of knowledge.

Another way to use the CE Framework to build connections across biology courses is to use it to develop an advance organizer (Ausubel, 1960). Advance organizers are educational tools that activate students’ prior knowledge and, through scaffolding, facilitate the assimilation of new knowledge and inform students’ mental schema about a particular field of study. Multiple studies have shown that student learning can be improved when an advance organizer is used to guide the incorporation of new information (Ausubel 1960, 1978; Barnes and Clawson, 1975; Mayer, 1979; Luiten et al., 1980). In introductory biology, students are introduced to a wide breadth of biological phenomena, which is expanded upon in upper-division courses. Using the CE Framework as a guide, introductory and upper-division instructors could collaborate to generate a simple biology advance organizer that bridges introductory-level biology knowledge and more advanced, discipline-specific knowledge. For example, students could generate a drawing or concept map of an animal cell and its cellular components (e.g., plasma membrane, nuclear membrane, and organelles) in introductory biology and use the CE Framework to discuss how the conceptual elements of structure and function are associated with each cellular component. In a subsequent course, like genetics or cellular biology, students could be asked to recreate or elaborate on their drawings or concept maps to investigate in greater detail how the structure of nucleic acids allows for the function of information flow, storage, and exchange at the molecular scale (i.e., the processes of transcription and translation).

As novice learners develop strategies to organize knowledge through a network of connections, their capacity to think as experts increases (Ambrose et al., 2010). Tools using the conceptual elements, like the examples given above, focus on a common centralized framework that can facilitate development of conceptual understanding by letting students practice organizing complex biological information iteratively as they advance from course to course through a curriculum, thus addressing the need to advance student learning beyond rote memorization (NRC, 1999; Ambrose et al., 2010; Momsen et al., 2010).

Developing and Aligning Learning Objectives and Assessments

Educators can use the CE Framework in the backward design process (Wiggens and McTighe, 2005) to write learning objectives that guide the development of curricular materials that address gaps in core concept coverage or to make explicit connections among the core concepts. To illustrate the utility of the CE Framework for curriculum design, imagine developing a unit in an introductory biology course that focuses on how fish exchange gases with the surrounding water (example from Table 3). Because structure and function is a primary concept underlying countercurrent gas exchange, the CE Framework could be used to design the learning objectives and associated learning materials so that they address the foundational elements of structure and function. The topic of countercurrent gas exchange would provide the specific information to describe the concept of structure and function, while the individual conceptual elements would provide a framework to define the breadth of coverage. For example, it would be important for students to understand how the structure of the gill arches directs water flow over the gills in a direction opposite that of blood flow and that the blood capillary walls and the gill epithelium are constructed of a single cell layer to allow for diffusion of oxygen from the water into the blood vessel (CE Framework SF1 and SF2). To challenge students to consider how changes in structure may influence function, instructors could expand learning materials to include the developmental stages of fish gills from fry to adult fish (SF3) or how permanent modifications due to disease may alter gill structure and function (SF4 and SF5). To make connections to other core concepts, instructors could have students consider how the expression of genetic information in specific cells corresponds to the development of the gill arches (IFES3) or how blood-oxygen levels are maintained and regulated to provide adequate oxygen for cellular respiration in muscle tissue of the fish (S2). Mapping the information about specific biological topics to the CE Framework as illustrated in this example provides a way to monitor and document whether core concept coverage is comprehensive, regardless of the biological topic taught.

The common language of the CE Framework also lends itself to writing isomorphic learning objectives and assessment questions across different courses. This can make the cross-cutting concepts more transparent to students and support the development of common assessment tools. Building on the examples described in Table 4, we present example isomorphic learning objectives for each selected conceptual element in Table 5. These isomorphic learning objectives could be modified into isomorphic assessment questions, thus allowing measurement of student learning of the same core concept across a variety of biological phenomena. This approach would allow a department to track students’ learning of the core concepts in courses spanning subdisciplines and scales as they progress through a curriculum. The authors have created and are testing a template for developing isomorphic assessment tools using the CE Framework. A manuscript describing this work is in development.

If adopting common or isomorphic assessment tools proves difficult for a department, the CE Framework could also be used as a common rubric for assessing core concept knowledge with data generated from diverse existing assessment tools. When used in this way as part of our local field-testing, the CE Framework yielded consistent scores across multiple graders from a wide variety of student responses. Graders simply scored for the presence or absence of each conceptual element, which allowed us to determine which conceptual elements were addressed and how frequently. Though using the CE Framework as a common rubric for grading student responses from different assessment tools could yield complex data, the benefit to this approach is that it allows individual instructors to retain their existing assessment tools, while simultaneously providing data on student learning that can be compared across multiple courses in a curriculum at the departmental level.

Evaluating Existing Curricula

Beyond its use to develop instructional materials to support student learning and the development of aligned learning objectives and assessments, the CE Framework may also be used at the department level to map core concept coverage across an entire curriculum. For departments seeking PULSE accreditation, the CE Framework can be used in tandem with the PULSE rubrics to identify specific gaps and strengths in their curriculum that they need to complete the PULSE “curriculum alignment” rubric, which measures to what extent the core concepts are covered in the curriculum (Aguirre et al., 2013).

The Vision and Change report offers very general descriptions of the core concepts. When used by individual instructors across a diversity of courses, these general descriptions can produce inconsistent data about core concept coverage that are difficult to align across a curriculum. For example, the components of evolution taught in both a molecular biology and ecology course may be the same, but the language and examples might be different, making it difficult to compare and map exactly what components of evolution are taught in the two courses. Likewise, the components of evolution taught in the two courses may actually be different, but identifying and documenting the differences can be challenging using the Vision and Change report general descriptions. The Vision and Change descriptions alone are not detailed enough for departments to get an accurate profile of which components of the core concepts are being taught across their curricula.

The CE Framework provides the detail needed to address this challenge by providing a way for instructors to be more specific about which components of the core concepts they are teaching. The framework’s common language transcends scales and subdisciplines, thus allowing calibration of reports of coverage and learning (and PULSE rubric rankings) across a diversity of courses. This empowers departments to generate accurate and comprehensive concept coverage maps of their general biology curricula.

To support using the framework in this way, we present two conceptual elements sample worksheets, one for individual courses and one for departments in Tables 6 and 7, respectively (see the Supplemental Material for a full set of worksheets). These worksheets allow instructors and departments to use the CE Framework to document which Vision and Change core concepts are addressed in their courses, which elements of those concepts are addressed, and at what biological scales. Using worksheets like these, instructors can characterize existing courses, determine how well they address the core concepts, and, if needed, develop strategies to modify them. Departments can use the information provided by the worksheets to facilitate the kinds of cross-departmental collaborations needed for reform efforts and to support their PULSE rubric self-ratings.

CONCLUSION

The transformation in undergraduate biology education called for in the Vision and Change report is underway at institutions across the nation (Pape-Lindstrom et al., 2015). As the work of transformation progresses, it has become clear that students, instructors, and departments could benefit from more detailed definitions of the core concepts. The BioCore Guide was an important first step in translating the core concepts into subdisciplinary language. The CE Framework takes a next step by providing detailed definitions that transcend subdisciplines and scales. Definitions that can be used in multiple ways from directly supporting student learning through the development of instructional materials, to developing aligned learning objectives and assessments, to evaluating the depth and breadth of core concept coverage across a biology curriculum. The detailed core concept curricular profiles that can be generated using the CE Framework can be used to guide and monitor reform of both individual courses and a department’s entire curriculum.

ACKNOWLEDGMENTS

REFERENCES