Dr. Andrew David’s research background inspired this project in which student groups work consecutively (not simultaneously) to solve a parasite mystery.
Assistant Professor and Director of Freshman Biology,Clarkson University in Potsdam, New York
PhD in Zoology, MS in Biology, BS in Biology
When Drew David, PhD, designed his upper-level parasitology course at Clarkson University in Potsdam, New York, he wanted to “build a sandbox” to explore his own teaching methods and projects. That included giving a new—and more realistic—twist to the traditional approach to group work on case studies.
“I’ve led group projects where you divvy up the class into teams, and each group does all of the tasks,” he says. “It’s fine, and it can work for helping students learn. But I wanted to simulate a real-world project where different groups of scientists work on different aspects of a project.” The upside (or downside) of these “sequential investigations” is that if anyone in the chain makes an error, the remainder of the work suffers.
Case in point: The scenario he provides for his parasitology class is about a parasite outbreak across Europe. “If the group responsible for detection—the first step in the process—misidentifies the parasite, then all the other groups will work under the incorrect premise,” he explains.
David, whose teaching approaches have been highlighted in Trends in Parasitology, uses this sequential-investigation approach in his zoology and marine biology courses, but he feels that it may work for disciplines outside of the sciences, as well.
Here, he shares the core steps involved in his sequential-learning project—and the key outcomes that instructors who adopt the approach can expect.
“Once students take ownership in this type of sequential-investigation project, it’s cool to see them understanding the stakes of why their work needs to be excellent. They really step up and get so involved in meeting the requirements.”
-Andrew David, PhD
Course: BY324 Parasitology
Course description: The natural history, ecology, and molecular biology of parasites are explored with an emphasis on life cycles, host/parasite interactions, and evolution of parasitism. Basic principles of epidemiology, transmission, diagnosis, treatment, and prevention are examined in parasites of medical, veterinary, and economic importance. Lectures will be supplemented by demonstrations of fixed materials and by exercises in identification and diagnoses.
David’s tips for leading a sequential case-study project
Below is the format David uses in his parasitology course for the parasite outbreak in Europe. As with many group projects, this one involves dividing the class into separate groups to achieve certain objectives within a single class period. Because the project is sequential, though, it presents a host of different challenges in both planning and execution. Here is how David addresses them as he guides students through the process:
Provide a crash course in how “sequential” work is different
Because this may be the first time students encounter this type of assignment, David is particularly clear about expectations, which are as follows:
- The project will be completed by three groups—assigned by David. (“I’ve already taught 99% of these students in earlier classes, so I know who is good at what and who will work well together,” he says.)
- Each group will be responsible for one step in the process of dealing with a disease outbreak.
- David will provide the data that students will use. All students also will have access to their textbooks, personal notes, and the Internet.
- The project time limit is 75 minutes total. There is no specific time limit for each group, but he does offer estimates, since Group 2 cannot begin until Group 1 is finished, for example.
- Each group will be allowed to leave once they have done their part, so that by the time Group 3 gets their information and data from Groups 1 and 2, Group 1 will have left the class.
Explain group roles and divide “pressure points” evenly
In typical group work, each group does the exact same steps simultaneously, so everyone faces the same level of challenges. In a sequential project, though, just splitting the project steps into thirds might lead to an imbalance in workload, says David.
“In terms of fairness, I try to create an equal division of labor between groups and create different crucial pressure points for each one,” he says. “These are elements that they have to get right for the project to work and for the entire team to solve the problem.” Here are the specifics for his parasite outbreak project:
Group 1: Identify the parasite
This group is given patient information, including symptoms, microscopic images from fecal smears, and profiles of infected towns so that they can also look for geographical clues that could help identify the parasite. (Time: 15 to 30 minutes)
Group 2: Design an intervention
This group’s purpose is to stem the spread of the parasite, which could be through direct treatment (prescribing medications/inoculations) and/or action (such as issuing a travel advisory). The correct action here depends upon how widespread the parasite is and how quickly it can spread. (Time: 10 to 15 minutes)
Group 3: Determine preventative measures
This group focuses on how to combat a recurrence of the disease. These students must consider what actions need to be taken to make sure infections do not continue even after the initial intervention is in place. (Time: 20 to 25 minutes)
Fun fact: For this particular project, students discover that the parasite “blood flukes” (genus: Schistosoma) are to blame. These flatworms, which are commonly found in fresh water, complete part of their life cycle in snails (their intermediate host) and can cause infections in humans known as schistosomiasis. Depending on the species, symptoms begin with a rash or itch and can progress to flu-like symptoms and, eventually, to malnutrition, organ damage, or fatality.
Penalize everyone if Group 1 errs—but offer a chance for redemption
In the following class session, David judges the results. Judging Group 1 is simple: Did they identify the correct parasite? If so, Groups 2 and 3 typically do well, too, so they are judged more on the specifics of their evaluations and recommendations.
If Group 1 diagnosed the parasite incorrectly, then the entire class fails the 100-point project. (This has happened only once, says David.) However, this is not as dire as it sounds: He allows the class to redeem the grade by completing a 70-point exercise on diagnosis, consisting of an individual essay reflecting on what factors might have led the incorrect diagnosis. “The purpose of this is to stimulate metacognition,” David explains.
Identify sticking points and insights during a class discussion
Following his assessment, David leads the entire class in a discussion of what went right and what went wrong. For example, together they consider:
- What lead to the correct/incorrect diagnoses?
- Was there enough information provided in the case files to make a clear, distinct diagnosis?
- For Group 3, were there any hidden transmission routes that the parasite could take that factored into the recommendations?
- Could there have been two parasites instead of one causing the infection, and if so, was it possible, based on the information given, to delineate both?
David says the exercise and following discussion help students learn about both the need for clear communication among the working groups and about the technical ability to interpret the biology of the parasite. He encourages students to ask questions of other groups about what challenges they encountered. “You get to see who the leaders are,” he says, and he notes that “students also develop their analytical skills, which is way more important today than typical regurgitation of facts and theories.”
In the future, David hopes to lead two or three different projects like this in each class so that each group can try each role: detection, intervention, and prevention. “If and when we have time, I will make sure students get to experience all aspects of a project,” he says. “But until then, all the students are learning the importance of collaboration and camaraderie.”