Biology instructors at all levels are presented with a growing evidence-based research literature for converting traditional, passive-learning lecture and laboratory courses into active-learning formats (1). This active-learning presents the opportunity to engage students with a wide range of teaching methods and assessment instruments. For example, students in laboratory courses can participate in authentic research projects, often in direct collaboration with professional researchers (e.g., 2). The challenge for courses where laboratory experience is not available is two-fold. The first is to engage students to develop the critical thinking skills necessary for them to define and solve biological problems. The second is to teach them how to communicate the significance of their work to their peers and others in the field. In their recent national survey, the Indiana University Center for Postsecondary Research (3) found that undergraduate Biology majors have more "high impact practices" (e.g., real research experiences outside of class, internships) than English, Psychology, and Business Administration majors. However, they report less in-class engagement (e.g., asking questions, giving presentations, and working in teams) than their peers. Indeed, this deficit in communication skills in Biology students is widely recognized in the literature (e.g., 4-7) and is a major focus of the Vision & Change initiative (8).
When addressing deficiencies in communication skills in their students, biology instructors face the risk of sacrificing course content for activities that could (or perhaps should) be taught in other, communications-focused courses. While specialized courses that focus on developing communication of biological concepts (e.g., 6, 7, 9) have a positive impact they also increase the course load in the curriculum, further straining instructors' limited time and resources. To address this issue, we have designed a non-laboratory teaching method based loosely on the "real-world" research experiences offered in laboratory courses (e.g., 10). The PEL approach helps students engage in the "real-world" teaching experience of collaborating with the instructor to investigate and evaluate biological subject matter (i.e., deciding what is worth learning). Students define their own learning outcomes, select appropriate assessments, and apply backward design strategies for assembling their own class presentations. In effect, students work as "lab groups" to design and execute teaching modules, then collect data to assess their own teaching effectiveness. Critical thinking about the subject matter is independently assessed via take home exams, mock grant review panels, and term papers.
By sharing the responsibility for designing and executing in-class activities, the instructor gives students greater ownership of their own learning while preserving rigor of the content. The PEL format requires students to effectively communicate the content in a variety of contexts, including group/peer discussion, collaborative discussion with the instructor, written and oral presentation to the class, and written evaluation of the presentations. When the instructor becomes familiar with the PEL format, it requires approximately the same amount of time as preparing and teaching a traditional lecture course (e.g., maximum of three hours outside of class per week).
In PEL (a lecture-free teaching model), small groups of students take turns running the entire class period, an approach that may be used for individual class periods, for multiple class periods, or even entire courses. Over the past three years, we have implemented PEL in advanced undergraduate and graduate courses in Cancer Biology and Cell-Extracellular Matrix Interactions. Initially, we used PEL in half of the class periods, alternating with traditional instructor lectures in the other half to provide the background material for the student presentations. Now, after a workshop in the first week, when the instructor teaches the class the PEL method, we use PEL in every class period for the remainder of the term. However, PEL is easily scalable to even portions of a single class. The student learning outcomes (SLOs) determine the length of the student presentations, which can be as simple as teaching a class how to use an online resource, or how a research technique works (e.g., RNA-Seq, super-resolved fluorescence microscopy).
Our current PEL courses (BIOL 4330/6330 and BIOL 4750/6750 at Rensselaer Polytechnic Institute) meet two times during the week, in 110 minute class periods. In each course groups of 2-to- 5 students give two-class presentations per semester. During their presentation week, the assigned group uses two consecutive class periods to present two complementary aspects of the same topic. Assessment of student learning outcomes occurs through a variety of instruments, including take home exams, in-class assignments and assessment activities, individual and group presentation scores, and peer evaluation, all guided by specific grading rubrics. The final exam format varies from semester to semester (e.g., grant proposals, grant reviews, etc.). The overall grade breakdown is shown below:
- Attendance: no unexcused absences allowed = 10%
- Two Weeks of Group Presentations - based on student audience surveys (5%), presenters' team survey (5%) and instructor's assessment (10%) from th presentation rubric = 20%
- Participation in class - instructor's participation rubric = 20%
- Two Take-home Exams (15% each) - instructor's exam performance rubric = 30%
- Final examination - In-class grant review - instructor's grant review rubric = 20%
Most commonly, the first class period of a student presentation is devoted to teaching the background necessary to complete an application exercise in the second class period. Because the students use backward design to assemble their presentations, they are always driven by explicit learning outcomes for each class period. Once all groups have given their first two-day presentation, the cycle repeats in the second half of the semester with new topics. The second presentation is a chance for each group to improve their presentation skills. Preparation for presentations requires students to devote approximately six hours of out-of-class work per topic. The preparation includes one required meeting with the instructor before every class period. Students present to the instructor the set learning outcomes, assessments, and strategy for presenting the topics. During the development period, students completed informed consent forms and the entire study was approved by the Institutional Review Board of Rensselaer Polytechnic Institute (Protocol #1275, approved July 29, 2013).
The instructor leads a workshop in the first week of the course. In this workshop students are taught how to use the backward design (11) and Bloom's Revised Taxonomy (12). Then students are assigned to groups of 3-4 students to work together for the reminder of the course. Each subsequent class period, overseen by the instructor, is devoted to student group presentations. Typically, all student presentations contain overtly stated learning outcomes mapped to Bloom's taxonomy. Each presentation follows a generally similar schedule, illustrated in Figure 1.
WEEK PRIOR TO A GROUP'S PRESENTATION
Executing PEL requires coordinating schedules of students and the instructor outside of class. We use the free online tool WhenIsGood (whenisgood.net) to find times when the instructor and presenting group are free to meet. Prior to the first meeting, the members of the presenting group must organize an outline of their two-day presentation, following the steps they learn in the workshop, including:
- Agree on topical coverage and scope of presentation
- Define learning outcomes and assessments for both class periods
- Map the learning outcomes and assessments to Bloom's taxonomy levels
- Discuss effective presentation strategies
- Assign preparation and presentation roles to group members
- Identify reading/homework assignments to assign to the students for the week
- Develop materials for in-class assessments for Day 1
At their first meeting with the instructor, the group presents these plans and the instructor provides feedback and suggestions for improvement. For example, the early groups in the semester often plan presentations that are too "ambitious" (they aim too high rather than too low on Bloom's Taxonomy levels). Overly ambitious SLOs require more time than the allotted class time, so the instructor helps them scale back their goals to some core elements, and offers suggestions for simplifying the assessment methods. Eventually they learn the logic of Bloom's, and start with low levels then build up to higher levels. The logic to follow the backward design based on Bloom's Taxonomy is discussed in the end-of-class debriefings and in the group meetings.
Once they reach consensus, the group uses the remaining time before class to:
- Develop a PowerPoint file for in-class use
- Email homework assignment to all students registered for the course (at least two days before the first class session)
PRESENTATION DAY 1
The teams complete the following classroom activities:
- Introduction/review of homework, 5-10 minutes
- Mini-lecture, video, and/or demonstration, 10-15 minutes
- Activity/assessment of first learning outcome, 10-15 minutes
- Peer-led small group discussion*, 15-20 minutes
- Activity/assessment of second learning outcome, 10-15 minutes
- Peer-assisted small group problem solving, 10-15 minutes
- Activity/assessment of third learning outcome, 10-15 minutes
Assessment of Presentations includes the following tasks:
The audience completes an anonymous Audience Presentation Evaluation Form (S1. Lecture-Free Classroom-Audience Presentation Evaluation Form).
- The instructor completes a presentation scoring rubric for each group member (S2. Lecture-Free Classroom-nstructor-Undergraduate Presentation Rubric and
- S3. Lecture-Free Classroom-Instructor-Graduate Presentation Rubric), 5 minutes
- Instructor-led public debriefing of presentation (whole class discussion), 5 minutes
Note: * The instructor records audience participation using the Instructor-Undergraduate Participation Rubric (S4) or Instructor-Graduate Participation Rubric (S5), as appropriate. Presenting groups of students are handed photocopies of these documents immediately after class. The Audience Presentation Evaluation Forms are made available in the Department of Biological Sciences office, and students must present identification to pick the documents up.
AFTER DAY 1 & BEFORE DAY 2
Following their first presentation, the presenting group receives immediate feedback from their Audience Presentation Evaluation Forms and completed Instructor Presentation Rubrics. They use this information, plus their own experience, to revise their proposed learning outcomes and/or assessments for Day 2 as necessary. The group meets the instructor to discuss the structure of their second presentation. Our course schedule (at RPI class days are: Monday and Thursday or Tuesday and Friday) has two days between classes, so the second meeting must take place in those two days. The group uses this meeting to:
- Debrief Day 1 presentation: what worked well, what did not, how could it be improved?
- Correct any misconceptions from Day 1: factual errors/omissions/misunderstandings that need to be revisited during Day 2
- Revise scope of subject matter, learning outcomes and assessments for Day 2
- Discuss effective presentation strategies
- Assign preparation and presentation roles to group members
- Revise reading/homework assignments for Day 2 (if necessary)
- Develop materials for in-class assessments for Day 2
As the semester progresses and students become familiar with the structure of the class, these second meetings typically shorten to 15-minute sessions. Following the meeting, the group prepares by:
- Developing a PowerPoint file for in-class use
- Emailing homework assignment to all students registered for the course, at least one day before class. Recall that our class meets Monday/Thursday or Tuesday/Friday, providing three days between class sessions. For classes that meet Monday/Thursday, the homework would need to be emailed by Wednesday morning.
PRESENTATION DAY 2
Day 2 follows a pattern similar to Day 1, including mini-lectures and peer-led group work interrupted by specific assessments targeted to the learning outcomes. These assessments vary widely, according to the learning outcomes of a presentation (examples provided below). The depth and rigor of the subject matter is typically greater on Day 2 because it builds on the foundation established on Day 1 together with the second homework assignment. As in Day 1, students complete Audience Presentation Evaluation Rubrics, and the instructor completes Instructor-Undergraduate/Graduate Presentation Forms and Participation Rubrics. At the end of class, presenting group members complete Teamwork Peer Evaluation Forms (S6) for each group member, including a self-evaluation, reflecting on each member's contribution to the two-day presentation project.
The presenting group uploads all media (e.g., PowerPoint files, research articles, in-class assessments, etc.) to the institute's Learning Management System (LMS). All students in the class have access to these files and use them as resources during their take home exams.
DEBRIEFING AFTER DAY 2
Though not required, most student groups like to meet briefly with the instructor, after the second presentation, to discuss their performance, and find out their grade. During this 10-20 minute meeting, we discuss:
- Positive and negative features of their presentation, and necessary improvements
- New ideas that future presentation teams might use
- What concepts were better understood by giving the presentation
- What suggestions does the group have for formatting exam questions concerning their topic?
Take-home exams include questions directly related to topics covered in the team presentations. Students often have excellent suggestions to connect their presentations to the exam questions. The strong relationship between presentations and exam questions calls for clear and organized PowerPoint presentations and in-class assessments.
All groups present one of their topics in the first half of the semester, and a class-wide debriefing/discussion about presentation qualities takes place before the second round of presentations begins. In this discussion, students reflect on the quality, rigor, and creativity of the presentations and discuss ways to improve them.
SAMPLE TWO-DAY STUDENT PRESENTATION PLAN
Presentation groups delivered 12 two-day presentations over the course of an entire semester. The first week in the semester was devoted to the instructor-lead workshop, and the last week was dedicated to the final exam project. For example, one group from the Cancer Biology class required the class to convert proteins in control of the cell cycle into characters in a movie plot, and then devise a new movie scene featuring these proteins/characters, based on the results of a research article (described in detail in 13). The specific learning outcomes for each day of class were:
1. Conclude the role of p53 in preserving genome stability (Bloom's level: Factual Understanding)
2. Relate the functions of p53, mdm2, and Arf to triggering apoptosis and cell cycle arrest (Bloom's level: Conceptual Applying)
3. Propose a mechanism for a cell's response to a situation in terms of a familiar story (Bloom's level: Procedural Creating)
1. Recall the functions of mdm2 and p53 and how the regulation of each affects apoptosis and cell cycle arrest (Bloom's level: Factual Remembering)
2. Graph the expected results when the conditions of a given experiment are altered (Bloom's level: Procedural Applying)
3. Invent an analogy to present biological data in a more familiar context (Bloom's level: Procedural Creating)
During the first day, the class was challenged to match characters from the movie Batman: The Dark Knight to specific cell cycle proteins/gene regulatory sequences, and defend their choices by analogy of protein function. For example, the p53 protein was assigned the role of Batman, because it prevents the destruction of the cell (Gotham City), while the protein mdm2 was assigned role of The Joker, because its primary function is to inhibit the function of p53. Under the guidance of the presenting group, an entire class period was used in the process of arriving at this matching. In this process the class was challenged to define the most important properties/functions of the listed proteins/gene sequences for themselves. Assessment activities occurred in stages, to ensure that all class members reached a consensus and could explain/defend their choices.
In the second class period, students were assigned a research article as homework. In class, they worked in small groups to translate the data in each of the six figures into a corresponding "story line" in the Batman universe. As a result, introducing a mutation in the promoter region of mdm2 (represented by the conversion of the Harvey Dent character into Two Face) enhanced activation of mdm2, reduced function of p53, and increased proliferation (rioting in Gotham City). Addition of a drug that inhibits the p21 transcription factor (poisoning Two Face) reduces mdm2 expression (The Joker is jailed) and apoptosis (destruction of the Gotham City) is reduced. When prompted with alternative scenarios (i.e., "What if?" questions) by the presenting group, the class was able to predict outcomes, diagram new outcomes as prospective data, invent new protein-based "characters" (e.g., police officers, petty criminals, news reporters), and translate these back and forth from cell signaling to the Batman universe. Finally, students acted out the story line in a mini-play.
Because all student groups are required to do in-class assessments of specific learning outcomes mapped to Bloom's taxonomy, generating evidence of specific learning skills is straightforward. Often, presenting groups develop their own assessment grading rubrics or collaborate with the audience to develop them. The instructor oversees these discussions, and intervenes when necessary to maintain the appropriate rigor. We are frequently astonished at the creativity our students display when collecting evidence. For example:
To simulate the challenges of clear communication in complex signaling networks, one group moved the entire class to a field outside. By moving the proximity/clustering/facing of individual students/proteins, they illustrated the logic of proximal and distal promoter sequences as regulators of gene transcription. Additional students served as methyl transferases, kinases, acetyl transferases, etc. Balloons, ribbons, hats, gloves, etc., modeled the resulting modifications to the DNA and chromatin, and the modified students "changed shape" as a result. The entire class eventually formed a regulatory complex, and was able to act out a variety of drugs that affect DNA replication and gene expression. Students who did not complete the assigned homework were, in consequence, not able to contribute to the model. (Bloom's level: Conceptual Evaluating)
To simulate the heterogeneity and complexity of the extracellular matrix, student groups used a variety of materials (e.g., pipe cleaners, paper clips, licorice candies, Play-Doh, paper strips) to build models of fibrillar collagens and network-forming collagens, fibronectins, laminins, and proteoglycans. They then compared the accuracy of their models by assembling them into polymers and applying tensile stress to the models (e.g., pulling on them; swinging them; attaching weights to them). A "collagen fiber" made of licorice has very different mechanical properties than one made from Play-Doh or paper strips. Students were then asked to explain why different models best captured specific properties of the extracellular matrix. As a culminating event, the "best" versions of each molecule type were attached to one another to form a "mock extracellular matrix." A beach ball was balanced on top of it to represent a cell. It became readily apparent that cells in contact with extracellular matrix cannot be spherical in shape. This observation set up the next group's presentations on receptor/matrix interactions. (Bloom's level: Factual Analyzing)
To model the practical limitations on biomedical research, the class was divided into small groups of 3-4, each led by a presenting student "advisor." Groups were tasked with developing a replacement artery using tissue-engineering methods (taught in an earlier class period). Groups received a "menu" to select from; and each item had a realistic cost in time and dollars. For example, hiring a technician would cost at least $40K per year, plus benefits. Students were asked to decide on the salary they would accept to work in such a position. If the minimum price was higher than $40K, the price rose accordingly. The task also required rent for research space and minimal safety facilities. Several different scenarios were tested that responded to the following questions: What could be accomplished in one year with an unlimited budget? What could be accomplished with no time limit but a $2M budget? How much time and money does it cost to raise money, and from what sources? Most students did not realize that fund-raising is itself quite expensive. The small groups shared their findings after several scenarios were tried out. Then students looked at examples of how real tissue engineering research companies assembled competitive business plans. Surprisingly, this exercise was developed by a group of students interested in achieving the learning outcome of teaching students to develop rigorous quality control standards in tissue engineering. When the class finally revisited the research paper that started the quality control discussion, many discovered their criteria for "success" had changed quite a bit. (Bloom's level: Metacognitive Creating).
Anyone contemplating a course reform will be concerned about ensuring their course's rigor. Our PEL model may magnify this concern since the instructors are not doing their usual lecturing. To address this issue, we broadened our course assessments to include the activities that the students performed in every class, and added these to our standard "test grade" and "presentation" metrics. These additional assessments included peer-to-peer interaction, communication skills, and student self-awareness. Rubrics for these assessments are provided in the supporting materials.
The complete list of assessments is as follows:
Instructor's scoring of each presenting student at the time of team presentation was achieved using the Instructor-Undergraduate (or Graduate) Presentation Rubric, covering: Organization (flow, timing, transitions); Content (depth and accuracy); Creativity; Use of Communication Aids; Use of Language; and Audience Interaction. Students could receive overall scores between 0-10 points. This contributes 10% of the course grade.
Audience scoring of each presenting student was captured using the Audience Presentation Evaluation Form. This form includes a 50-point scale covering 10 presentation skills: How well they defined their learning outcomes; How well they achieved their learning outcomes; Clarity in discussing and presenting the material; Knowledge of content presented; Quality of questions/activities to stimulate audience interaction and participation; Quality of answering audience/group questions; Overall quality of visuals; Presentation professionalism; Effective time management; and Audience confidence in the presenter. Space is available on the forms to provide written feedback on the following topics: What was good about his/her part of the presentation? What do you suggest to help him/her improve? Would you hire him/her? Why/why not? What aspects of the overall presentation did you especially like? How could the overall presentation be improved?
Audience Presentation Evaluation Forms are anonymous, completed during the last five minutes of each class period, and handed in immediately. They contribute 5% of the course grade.
Student self-evaluations: Presenting group members scored themselves and each other at the end of each two-day presentation period, using the Teamwork Peer Evaluation Form, which includes a 20 point scale for the following attributes: Preparation (Research, reading, and assignment completed); Attendance (On-time and stayed for duration of meetings); Participation (Contributed best academic ability); Interpersonal Relations (Positive and productive); Between Meeting Communication (Initiated and responded appropriately). The forms also included two optional, unscored questions: What are the most important teamwork concepts (not course content) you have learned from this experience? How will you put this experience to use in the future? This self-evaluation contributes 5% of the course grade.
Class participation was also assessed by the instructor. The Instructor-Undergraduate (and Graduate) Participation Rubric uses a Likert scale (Distinguished, Proficient, Poor, Unacceptable) for the following attributes: Answering a question, Asking a question, and Active listening. Based on the instructor's evaluation students could earn up to 10 points per class period. This contributes 20% of the course grade.
Written exams were take home essay format and were graded by Undergraduate and Graduate Exam Grading Rubrics evaluating each exam question for Focus, Depth, Organization, and Language. In addition to instructor evaluation of written exams, students were required to classify their answer to each exam question using Bloom's Taxonomy. This contributes 30% of the course grade.
The Final Examination and class Attendance contribute 20% and 10% of the course grade, respectively.
As the above assessment descriptions show, in our PEL classes, student learning is assessed daily (Audience Presentation Evaluation Forms, Instructor Presentation Rubrics, Instructor Participation Rubrics), weekly (Teamwork Peer Evaluation Form), bi-monthly (two midterm examinations; see Supporting Documents S7 and S8 for undergraduate and graduate exam grading rubrics, respectively), and at the end of the semester (final exam).
The homework assigned by the student groups during their presentations (e.g., Read the attached article and come prepared to discuss Figures 3, 4 and 6), is not graded directly, but is reflected in the participation grade for each day. In our experience, students who opt to skip the homework are poorly equipped to complete the in-class assessments and/or do not participate in class discussions. Their deficiency is reflected in their participation grade. In addition, habitually unprepared students (typically one per year) are subsequently ostracized by the class, and eventually either drop the class or reverse course and start completing the homework. All exams are take-home, and the final exam format varies from semester to semester (e.g., mock grant proposals, grant reviews, etc.). Aside from the backward design based on Bloom's taxonomy workshop in the first week, the instructor does no formal lecturing during the semester.
Results from our experience (across three years of developing and applying our PEL teaching method), show that students’ critical thinking skills on take-home exams improved dramatically. For example, the rigor of exam questions, as determined by the percentage of essay-style exam questions mapped to Bloom’s Taxonomy (Procedural Create level), increased from 28% in first year to 75% in third year. Likewise, the students’ ability to correctly answer questions at this level increased from an average of 21±12% to 61±19%. These changes reflect both the instructor’s increasing confidence in asking higher-order questions, and students’ ability to recognize the expected rigor of these questions. From these observations, we conclude that adoption of the no-lecture, PEL method increases active learning in our students without compromising the rigor in our courses. This was reflected by student responses to exam questions requiring higher order critical thinking skills based on Bloom’s taxonomy. In conclusion, PEL is easily scalable and can be applied for the entire course, for a single class period, or even a portion of a single class. Instructors should be familiar with backward design techniques, Student Learning Outcomes (SLO) mapped to Bloom’s Revised Taxonomy (14), and be able to initially instruct the students on the importance of using SLOs mapped on Bloom’s taxonomy.
- S1: Audience Presentation Evaluation Form
- S2: Instructor-Undergraduate Presentation Rubric
- S3: Instructor-Graduate Presentation Rubric
- S4: Instructor-Undergraduate Participation Rubric
- S5: Instructor-Graduate Participation Rubric
- S6: Teamwork Peer Evaluation Form
- S7: Undergraduate Exam Grading Rubric
- S8: Graduate Exam Grading Rubric
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