Mary Pat Wenderoth

Active learning increases student performance in science, engineering, and mathematics

Significance The President’s Council of Advisors on Science and Technology has called for a 33% increase in the number of science, technology, engineering, and mathematics (STEM) bachelor’s degrees completed per year and recommended adoption of empirically validated teaching practices as critical to achieving that goal. The studies analyzed here document that active learning leads to increases in examination performance that would raise average grades by a half a letter, and that failure rates under traditional lecturing increase by 55% over the rates observed under active learning. The analysis supports theory claiming that calls to increase the number of students receiving STEM degrees could be answered, at least in part, by abandoning traditional lecturing in favor of active learning. To test the hypothesis that lecturing maximizes learning and course performance, we metaanalyzed 225 studies that reported data on examination scores or failure rates when comparing student performance in undergraduate science, technology, engineering, and mathematics (STEM) courses under traditional lecturing versus active learning. The effect sizes indicate that on average, student performance on examinations and concept inventories increased by 0.47 SDs under active learning (n = 158 studies), and that the odds ratio for failing was 1.95 under traditional lecturing (n = 67 studies). These results indicate that average examination scores improved by about 6% in active learning sections, and that students in classes with traditional lecturing were 1.5 times more likely to fail than were students in classes with active learning. Heterogeneity analyses indicated that both results hold across the STEM disciplines, that active learning increases scores on concept inventories more than on course examinations, and that active learning appears effective across all class sizes—although the greatest effects are in small (n ≤ 50) classes. Trim and fill analyses and fail-safe n calculations suggest that the results are not due to publication bias. The results also appear robust to variation in the methodological rigor of the included studies, based on the quality of controls over student quality and instructor identity. This is the largest and most comprehensive metaanalysis of undergraduate STEM education published to date. The results raise questions about the continued use of traditional lecturing as a control in research studies, and support active learning as the preferred, empirically validated teaching practice in regular classrooms.

Increased Course Structure Improves Performance in Introductory Biology

We tested the hypothesis that highly structured course designs, which implement reading quizzes and/or extensive in-class active-learning activities and weekly practice exams, can lower failure rates in an introductory biology course for majors, compared with low-structure course designs that are based on lecturing and a few high-risk assessments. We controlled for 1) instructor effects by analyzing data from quarters when the same instructor taught the course, 2) exam equivalence with new assessments called the Weighted Blooms Index and Predicted Exam Score, and 3) student equivalence using a regression-based Predicted Grade. We also tested the hypothesis that points from reading quizzes, clicker questions, and other “practice” assessments in highly structured courses inflate grades and confound comparisons with low-structure course designs. We found no evidence that points from active-learning exercises inflate grades or reduce the impact of exams on final grades. When we controlled for variation in student ability, failure rates were lower in a moderately structured course design and were dramatically lower in a highly structured course design. This result supports the hypothesis that active-learning exercises can make students more skilled learners and help bridge the gap between poorly prepared students and their better-prepared peers.

Teaching the Process of Science: Faculty Perceptions and an Effective Methodology

Most scientific endeavors require science process skills such as data interpretation, problem solving, experimental design, scientific writing, oral communication, collaborative work, and critical analysis of primary literature. These are the fundamental skills upon which the conceptual framework of scientific expertise is built. Unfortunately, most college science departments lack a formalized curriculum for teaching undergraduates science process skills. However, evidence strongly suggests that explicitly teaching undergraduates skills early in their education may enhance their understanding of science content. Our research reveals that faculty overwhelming support teaching undergraduates science process skills but typically do not spend enough time teaching skills due to the perceived need to cover content. To encourage faculty to address this issue, we provide our pedagogical philosophies, methods, and materials for teaching science process skills to freshman pursuing life science majors. We build upon previous work, showing student learning gains in both reading primary literature and scientific writing, and share student perspectives about a course where teaching the process of science, not content, was the focus. We recommend a wider implementation of courses that teach undergraduates science process skills early in their studies with the goals of improving student success and retention in the sciences and enhancing general science literacy.

Gender gaps in achievement and participation in multiple introductory biology classrooms.

Although females outnumber males in biology, this study of 23 different introductory biology classrooms reveals systematic gender disparities in student performance on exams and student participation when instructors ask students to volunteer answers to instructor-posed questions.

PORTAAL: A Classroom Observation Tool Assessing Evidence-Based Teaching Practices for Active Learning in Large Science, Technology, Engineering, and Mathematics Classes.

PORTAAL, a new evidence-based classroom observation tool, identifies 21 elements of classroom best practices for active learning that have been correlated with positive student outcomes in the education literature. After only 5 h of training, instructors can reliably use this tool to determine their alignment with these teaching practices.

Caution, Student Experience May Vary: Social Identities Impact a Student's Experience in Peer Discussions.

This study found that self-reported preferred roles in peer discussions in introductory biology classrooms can be predicted by social identities and that barriers to participation in peer discussions may impact certain student groups more than others.

BioCore Guide: A Tool for Interpreting the Core Concepts of Vision and Change for Biology Majors

Using a grassroots approach to incorporate feedback from more than 240 biologists, the authors have taken the core concepts of Vision and Change and created the BioCore Guide—a set of general principles and specific statements that expand upon the core concepts, creating a framework that biology departments can use to align with the goals of Vision and Change.

Ultrastructural distribution of myosin heavy chain mRNA in cardiac tissue: a comparison of frozen and LR White embedment.

Electron microscopy (EM) in situ hybridization provides the higher resolution necessary to determine the spatial relationship between a specific mRNA and the organelle containing the protein encoded by that message. EM in situ hybridization was used to determine the subcellular myosin heavy chain (MHC) mRNA distribution with respect to the myofibril in normal cardiac tissue. Sections of frozen or acrylic-embedded tissue were compared for ultrastructural integrity and content of endogenous mRNA. Papillary muscles dissected from hearts of normal rabbits were aldehyde-fixed and either frozen or embedded in LR White. EM in situ hybridization with no riboprobe, vector sequence, same-sense, and anti-sense biotinylated riboprobes was detected by indirect immunocytochemistry. Labeling density using an antisense probe was highest over the intermyofibrillar space, with an average signal five times that of background. Background labeling by nonspecific sense probe was consistently low but not random, also having the highest density of gold clusters over the intermyofibrillar space. Ultracryomicrotomy yielded a higher absolute number of gold clusters, but sections were fragmented and disrupted striated muscle morphology. LR White embedment maintained ultrastructural integrity but gave a lower absolute signal. Fortunately, MHC mRNA is an abundant message and can tolerate the decreased sensitivity of LR White.

Distribution of myosin heavy chain mRNA in normal and hyperthyroid heart

Hyperthyroid treatment produces rapid cardiac cell hypertrophy with all subcellular components increasing in an orderly manner. We compare normal and hyperthyroid tissue in order to relate changes in distribution of myosin mRNA during rapid assembly of myofibrils. At the light microscopic level, in situ hybridization of the ventricular cells shows myosin heavy chain mRNA to be distributed in a spoke-like pattern radiating from the nucleus. Electron microscopy provides the higher resolution necessary to determine mRNA distribution with respect to adjacent sarcomeric and cytoskeletal structures. Papillary muscles were removed from hyperthyroid and normal rabbits, aldehyde fixed, and embedded in LR white. Biotinated riboprobe transcribed from 0.5 kb in the coding region of terminal portion of the rod of alpha-myosin was hybridized and detected by immunocytochemical methods using 5 nm immunoglobulin G gold conjugates. Electron microscopy in situ hybridization runs with same-sense and anti-sense riboprobes were processed and ten micrographs randomly taken from each. Specific cytoplasmic densities of myosin mRNA were calculated by counting clusters of five or more gold particles over respective tissue components after subtraction of background counts. For both normal myocytes and hyperthyroid myocytes, the density of myosin mRNA was about 15 times higher in the cytoskeletal-rich inter-myofibrillar space than in the myofibrils. About half of the myosin mRNA in this inter-myofibrillar region is found within 10 nm of the peripheral filament, but no excess sarcomeric accumulation was seen beside the A-Band. It appears that most of the myosin is translated from mRNA within the inter-myofibrillar space along the entire length of the myofibril periphery. The emerging myosin heavy chain is not directly anchored to the thick filaments in either normal or rapidly growing cardiac cells.

How should we teach tree-thinking? An experimental test of two hypotheses

BackgroundPhylogenies are ubiquitous in college-level biology textbooks, yet many college students continue to struggle to interpret them correctly. Multiple activities and frameworks for teaching phylogenies have been proposed to address this problem. In an introductory biology course for majors, we tested two contrasting hypotheses about the best way for students to learn the basic principles of ‘tree-thinking’.MethodsWe constructed two 30-minute, pencil-and-paper-based guided group activities: one focused on using a character matrix to build a tree and one focused on analyzing an existing tree. Groups of three students completed one of these activities during one class session of a large lecture course. All students completed an identical assessment the night of the activity.ResultsWe confirmed that students in the two groups were of equal academic ability, and found that students in the ‘build your own tree’ treatment performed significantly better on the assessment than students in the ‘analyze an existing tree’ treatment. We also had first-year graduate students in a Biology PhD program complete the assessment, without doing the activity beforehand. The scores of undergraduates who had done a modified version of the tree building activity were indistinguishable from those of the graduate students.ConclusionWe recommend simple tree-building activities be a standard part of training for tree-thinking in introductory biology.