This study examined children's drawings to explain children's conceptual understanding of plant structure and function. The study explored whether the children's drawings accurately reflect their conceptual understanding about plants in a manner that can be interpreted by others. Drawing, survey, interview, and observational data were collected from 182 students in grades K and 1 in rural southeastern United States. Results demonstrated the children held a wide range of conceptions concerning plant structure and function. These young children held very simple ideas about plants with respect to both their structure and function. Consistent with the drawings, the interviews presented similar findings.

In response to the American Association for the Advancement of Science's Vision and Change in Undergraduate Biology Education initiative, we infused authentic, plant-based research into majors’ courses at a public liberal arts university. Faculty members designed a financially sustainable pedagogical approach, utilizing vertically integrated curricular modules based on undergraduate researchers’ field and laboratory projects. Our goals were to 1) teach botanical concepts, from cells to ecosystems; 2) strengthen competencies in statistical analysis and scientific writing; 3) pique plant science interest; and 4) allow all undergraduates to contribute to genuine research. Our series of inquiry-centered exercises mitigated potential faculty barriers to adopting research-rich curricula, facilitating teaching/research balance by gathering publishable scholarly data during laboratory class periods. Student competencies were assessed with pre- and postcourse quizzes and rubric-graded papers, and attitudes were evaluated with pre- and postcourse surveys. Our revised curriculum increased students’ knowledge and awareness of plant science topics, improved scientific writing, enhanced statistical knowledge, and boosted interest in conducting research. More than 300 classroom students have participated in our program, and data generated from these modules’ assessment allowed faculty and students to present 28 contributed talks or posters and publish three papers in 4 yr. Future steps include analyzing the effects of repeated module exposure on student learning and creating a regional consortium to increase our project's pedagogical impact.

We investigate how students connect explanations and arguments from evidence about plant growth and metabolism—two key practices described by the Next Generation Science Standards. This study reports analyses of interviews with 22 middle and high school students postinstruction, focusing on how their sense-making strategies led them to interpret—or misinterpret—scientific explanations and arguments from evidence. The principles of conservation of matter and energy can provide a framework for making sense of phenomena, but our results show that some students reasoned about plant growth as an action enabled by water, air, sunlight, and soil rather than a process of matter and energy transformation. These students reinterpreted the hypotheses and results of standard investigations of plant growth, such as van Helmont's experiment, to match their own understanding of how plants grow. Only the more advanced students consistently interpreted mass changes in plants or soil as evidence of movement of matter. We also observed that a higher degree of scaffolding during some of the interview questions allowed mid-level students to improve their responses. We describe our progress and challenges developing teaching materials with scaffolding to improve students’ understanding of plant growth and metabolism.

Genetics instruction in introductory biology is often confined to Mendelian genetics and avoids the complexities of variation in quantitative traits. Given the driving question “What determines variation in phenotype (Pv)? (Pv=Genotypic variation Gv + environmental variation Ev),” we developed a 4-wk unit for an inquiry-based laboratory course focused on the inheritance and expression of a quantitative trait in varying environments. We utilized Brassica rapa Fast Plants as a model organism to study variation in the phenotype anthocyanin pigment intensity. As an initial curriculum assessment, we used free word association to examine students’ cognitive structures before and after the unit and explanations in students’ final research posters with particular focus on variation (Pv = Gv + Ev). Comparison of pre- and postunit word frequency revealed a shift in words and a pattern of co-occurring concepts indicative of change in cognitive structure, with particular focus on “variation” as a proposed threshold concept and primary goal for students’ explanations. Given review of 53 posters, we found ∼50% of students capable of intermediate to high-level explanations combining both Gv and Ev influence on expression of anthocyanin intensity (Pv). While far from “plug and play,” this conceptually rich, inquiry-based unit holds promise for effective integration of quantitative and Mendelian genetics.

Learning to identify organisms is extraordinarily difficult, yet trained field biologists can quickly and easily identify organisms at a glance. They do this without recourse to the use of traditional characters or identification devices. Achieving this type of recognition accuracy is a goal of many courses in plant systematics. Teaching plant identification is difficult because of variability in the plants’ appearance, the difficulty of bringing them into the classroom, and the difficulty of taking students into the field. To solve these problems, we developed and tested a cognitive psychology–based computer program to teach plant identification. The program incorporates presentation of plant images in a homework-based, active-learning format that was developed to stimulate expert-level visual recognition. A controlled experimental test using a within-subject design was performed against traditional study methods in the context of a college course in plant systematics. Use of the program resulted in an 8–25% statistically significant improvement in final exam scores, depending on the type of identification question used (living plants, photographs, written descriptions). The software demonstrates how the use of routines to train perceptual expertise, interleaved examples, spaced repetition, and retrieval practice can be used to train identification of complex and highly variable objects.

Plants, to many, are simply not as interesting as animals. Students typically prefer to study animals rather than plants and recall plants more poorly, and plants are underrepresented in the classroom. The observed paucity of interest for plants has been described as plant blindness, a term that is meant to encapsulate both the tendency to neglect plants in the environment and the lack of appreciation for plants’ functional roles. While the term plant blindness suggests a perceptual or attentional component to plant neglect, few studies have examined whether there are real differences in how plants and animals are perceived. Here, we use an established paradigm in visual cognition, the “attentional blink,” to compare the extent to which images of plants and animals capture attentional resources. We find that participants are better able to detect animals than plants in rapid image sequences and that visual attention has a different refractory period when a plant has been detected. These results suggest there are fundamental differences in how the visual system processes plants that may contribute to plant blindness. We discuss how perceptual and physiological constraints on visual processing may suggest useful strategies for characterizing and overcoming zoocentrism.

Over the past decade, repeated calls have been made to incorporate more active teaching and learning in undergraduate biology courses. The emphasis on inquiry-based teaching is especially important in laboratory courses, as these are the courses in which students are applying the process of science. To determine the current state of research on inquiry-based teaching in undergraduate biology laboratory courses, we reviewed the recent published literature on inquiry-based exercises. The majority of studies in our data set were in the subdisciplines of biochemistry, cell biology, developmental biology, genetics, and molecular biology. In addition, most exercises were guided inquiry, rather than open ended or research based. Almost 75% of the studies included assessment data, with two-thirds of these studies including multiple types of assessment data. However, few exercises were assessed in multiple courses or at multiple institutions. Furthermore, assessments were rarely based on published instruments. Although the results of the studies in our data set show a positive effect of inquiry-based teaching in biology laboratory courses on student learning gains, research that uses the same instrument across a range of courses and institutions is needed to determine whether these results can be generalized.

At the college level, the effectiveness of active-learning interventions is typically measured at the broadest scales: the achievement or retention of all students in a course. Coarse-grained measures like these cannot inform instructors about an intervention's relative effectiveness for the different student populations in their classrooms or about the proximate factors responsible for the observed changes in student achievement. In this study, we disaggregate student data by racial/ethnic groups and first-generation status to identify whether a particular intervention—increased course structure—works better for particular populations of students. We also explore possible factors that may mediate the observed changes in student achievement. We found that a “moderate-structure” intervention increased course performance for all student populations, but worked disproportionately well for black students—halving the black–white achievement gap—and first-generation students—closing the achievement gap with continuing-generation students. We also found that students consistently reported completing the assigned readings more frequently, spending more time studying for class, and feeling an increased sense of community in the moderate-structure course. These changes imply that increased course structure improves student achievement at least partially through increasing student use of distributed learning and creating a more interdependent classroom community.

We investigated some of the key features of effective active learning by comparing the outcomes of three different methods of implementing active-learning exercises in a majors introductory biology course. Students completed activities in one of three treatments: discussion, writing, and discussion + writing. Treatments were rotated weekly between three sections taught by three different instructors in a full factorial design. The data set was analyzed by generalized linear mixed-effect models with three independent variables: student aptitude, treatment, and instructor, and three dependent (assessment) variables: change in score on pre- and postactivity clicker questions, and coding scores on in-class writing and exam essays. All independent variables had significant effects on student performance for at least one of the dependent variables. Students with higher aptitude scored higher on all assessments. Student scores were higher on exam essay questions when the activity was implemented with a writing component compared with peer discussion only. There was a significant effect of instructor, with instructors showing different degrees of effectiveness with active-learning techniques. We suggest that individual writing should be implemented as part of active learning whenever possible and that instructors may need training and practice to become effective with active learning.

Although gender gaps have been a major concern in male-dominated science, technology, engineering, and mathematics disciplines such as physics and engineering, the numerical dominance of female students in biology has supported the assumption that gender disparities do not exist at the undergraduate level in life sciences. Using data from 23 large introductory biology classes for majors, we examine two measures of gender disparity in biology: academic achievement and participation in whole-class discussions. We found that females consistently underperform on exams compared with males with similar overall college grade point averages. In addition, although females on average represent 60% of the students in these courses, their voices make up less than 40% of those heard responding to instructor-posed questions to the class, one of the most common ways of engaging students in large lectures. Based on these data, we propose that, despite numerical dominance of females, gender disparities remain an issue in introductory biology classrooms. For student retention and achievement in biology to be truly merit based, we need to develop strategies to equalize the opportunities for students of different genders to practice the skills they need to excel.

We compared learning cycle and expository formats for teaching about plant biodiversity in an inquiry-oriented university biology lab class (n = 465). Both formats had preparatory lab activities, a hands-on lab, and a postlab with reflection and argumentation. Learning was assessed with a lab report, a practical quiz in lab, and a multiple-choice exam in the concurrent lecture. Attitudes toward biology and treatments were also assessed. We used linear mixed-effect models to determine impacts of lab style on lower-order cognition (LO) and higher-order cognition (HO) based on Bloom's taxonomy. Relative to the expository treatment, the learning cycle treatment had a positive effect on HO and a negative effect on LO included in lab reports; a positive effect on transfer of LO from the lab report to the quiz; negative impacts on LO quiz performance and on attitudes toward the lab; and a higher degree of perceived difficulty. The learning cycle treatment had no influence on transfer of HO from lab report to quiz or exam; quiz performance on HO questions; exam performance on LO and HO questions; and attitudes toward biology as a science. The importance of LO as a foundation for HO relative to these lab styles is addressed.

This study was conducted in an attempt to investigate the effectiveness of an educational card game we developed for learning human immunology. Two semesters of evaluation were included to examine the impact of the game on students’ understanding and perceptions of the game-based instruction. Ninety-nine senior high school students (11th graders) were recruited for the first evaluation, and the second-semester group consisted of 72 students (also 11th graders). The results obtained indicate that students did learn from the educational card game. Moreover, students who learned from playing the game significantly outperformed their counterparts in terms of their understanding of the processes and connections among different lines of immunological defense (first semester: t = 2.92, p < 0.01; second semester: t = 3.45, p < 0.01) according to the qualitative analysis of an open-ended question. They generally had positive perceptions toward the game-based instruction and its learning efficiency, and they felt the game-based instruction was much more interesting than traditional didactic lectures (first semester: t = 2.79, p < 0.01; second semester: t = 2.41, p < 0.05). This finding is evidence that the educational card game has potential to facilitate students’ learning of how the immune system works. The implications and suggestions for future work are further discussed.

Threshold concepts (TCs) are concepts that, when mastered, represent a transformed understanding of a discipline without which the learner cannot progress. We have undertaken a process involving more than 75 faculty members and 50 undergraduate students to identify a working list of TCs for biochemistry. The process of identifying TCs for biochemistry was modeled on extensive work related to TCs across a range of disciplines and included faculty workshops and student interviews. Using an iterative process, we prioritized five concepts on which to focus future development of instructional materials. Broadly defined, the concepts are steady state, biochemical pathway dynamics and regulation, the physical basis of interactions, thermodynamics of macromolecular structure formation, and free energy. The working list presented here is not intended to be exhaustive, but rather is meant to identify a subset of TCs for biochemistry for which instructional and assessment tools for undergraduate biochemistry will be developed.

Mutation is the key molecular mechanism generating phenotypic variation, which is the basis for evolution. In an introductory biology course, we used a model-based pedagogy that enabled students to integrate their understanding of genetics and evolution within multiple case studies. We used student-generated conceptual models to assess understanding of the origin of variation. By midterm, only a small percentage of students articulated complete and accurate representations of the origin of variation in their models. Targeted feedback was offered through activities requiring students to critically evaluate peers’ models. At semester's end, a substantial proportion of students significantly improved their representation of how variation arises (though one-third still did not include mutation in their models). Students’ written explanations of the origin of variation were mostly consistent with their models, although less effective than models in conveying mechanistic reasoning. This study contributes evidence that articulating the genetic origin of variation is particularly challenging for learners and may require multiple cycles of instruction, assessment, and feedback. To support meaningful learning of the origin of variation, we advocate instruction that explicitly integrates multiple scales of biological organization, assessment that promotes and reveals mechanistic and causal reasoning, and practice with explanatory models with formative feedback.

Interest in student conception of experimentation inspired the development of a fully validated 14-question inventory on experimental design in biology (BEDCI) by following established best practices in concept inventory (CI) design. This CI can be used to diagnose specific examples of non–expert-like thinking in students and to evaluate the success of teaching strategies that target conceptual changes. We used BEDCI to diagnose non–expert-like student thinking in experimental design at the pre- and posttest stage in five courses (total n = 580 students) at a large research university in western Canada. Calculated difficulty and discrimination metrics indicated that BEDCI questions are able to effectively capture learning changes at the undergraduate level. A high correlation (r = 0.84) between responses by students in similar courses and at the same stage of their academic career, also suggests that the test is reliable. Students showed significant positive learning changes by the posttest stage, but some non–expert-like responses were widespread and persistent. BEDCI is a reliable and valid diagnostic tool that can be used in a variety of life sciences disciplines.

We have created an inventory to characterize the teaching practices used in science and mathematics courses. This inventory can aid instructors and departments in reflecting on their teaching. It has been tested with several hundred university instructors and courses from mathematics and four science disciplines. Most instructors complete the inventory in 10 min or less, and the results allow meaningful comparisons of the teaching used for the different courses and instructors within a department and across different departments. We also show how the inventory results can be used to gauge the extent of use of research-based teaching practices, and we illustrate this with the inventory results for five departments. These results show the high degree of discrimination provided by the inventory, as well as its effectiveness in tracking the increase in the use of research-based teaching practices.