|Vol. 18, No. 31||May 13, 1999|
It all began when a farmer in Kent, England, noticed his herd behaving strangely. His cows had begun walking with a peculiar gait, seemed to be in a constant state of apprehension and were hypersensitive to sound and touch. A few became unmanageably aggressive. (Have you ever tried to milk a demented cow?)" --From Thinking Toward Solutions: Problem-Based Learning Activities for General Biology
Coming up with a solution to such a problem is how problem-based learning works. No, not by figuring out how to milk a berserk bovine, but by using the skills taught in biology class to figure out why a cow's gone mad. In the case of the antagonistic Angus, the mystery is whatif anymicroscopic organism is the likely culprit?
The situation described above is from a justpublished student manual entitled Thinking Toward Solutions: Problem-Based Learning Activities for General Biology, compiled by Deborah E. Allen, biological sciences, and Barbara J. Duch, Mathematics and Science Education Resource Center (MSERC). The workbook consists of 25 scenarios and sets of questions that require scientific investigation to be answered.
Meant to act as a problem-based teaching tool for general biology students, the book is full of engaging and oddball situations that represent complicated, real-life mysteries that can only be solved through an understanding of biology.
To use the book, students form small teams, which must able to work together, communicate and mesh the information they research into facts that solve the problem. That teaching methodology is the foundation of problem-based learning (PBL).
PBL gives students a goal, a mystery to solve, an immediate reason to master the skills they're being taught, and it helps them develop critical thinking, cooperative team work, communication skills and a desire to learn. Basically, PBL answers the questionWhy do we have to learn this?
In 1998, UD was awarded a $615,000 grant from the Pew Charitable Trusts to create University-wide PBL courses with a focus on large introductory classes. At that time, PBL was being used mainly in small-to medium-sized classes.
John Cavanaugh, academic programming and planning, coauthored the grant proposal with Duch and oversees the expansion program that prepares faculty to use PBL techniques. Faculty development is needed because, as Duch explained, PBL requires faculty to think differently about their role in the classroom. It requires students to work in groups with the teacher as more of a facilitator than a lecturer. "When students work in groups, everyone's performance rises. There is peer pressure to come to class and to be prepared to contribute," Duch said.
The book is put together like a series of short stories with widely divergent themes. "Water Water Everywhere" begins, "Maria, Alicia, Carlos and Ben were born to sail." It goes on to describe the beginning of a sailboat trip around the world that ends with a storm, the sinking of the boat and the four of them in a lifeboat with no food and only one small container of water. As if that wasn't bad enough, Maria is three months pregnant and Ben is unconscious.
At this point, students are asked whether or not the four should drink seawater to survive and why or why not. If the answer is no, they are asked if there are other options for coping with a lack of fluids.
The story goes on to say that the quartet is rescued quickly and taken to a hospital to be treated for dehydration. They are given a series of tests. The results of each person's tests are part of the problem. From the test results, students must determine what kind of fluid the doctor recommended for Maria, Alicia and Carlos and why he thinks Ben may need special treatment.
Students are then asked to estimate how dehydrated each person is and how much fluid each will need to return to normal. They are given a formula to calculate both. Calculations are different for males and females and different still for pregnant Maria.
The last part of the problem describes how this incident would affect other biological systems like the kidneys. Students need to know about the hormones that help regulate the body's salt and water content, how the body gains and loses water and salt, and the structure and function relationships of the endocrine glands involved in the control of salt and water.
"Anna or Anastasia" opens with "One summer's night in 1918, a fusillade of shots rang out from a room deep within the Ipatiev House...." It describes the Bolsheviks' brutal execution of Tsar Nicholas II, his family and servants. The story follows the exhumations of the bodies and ultimate DNA search to uphold or discount Anna Anderson's claim that she was Anastasia Romanov. The questions center on the DNA tests.
"When Twins Marry Twins" is about cell division; in "The Curse of the Mummy" (subtitled"If It's Dead, It Sphinx") by Jane Nobel-Harvey, biological sciences, students look for the infectious agents that killed Professor Noseitall after he opened Pharaoh Hotsitotsi III's tomb. "Where Have All the Froggies Gone" and "On the Road to Extinction," coauthored by Richard Donham, MSERC, deal with discovering why species are endangered.
The book is supported by a website that offers online materials to help solve the mysteries.
Saunders College Publishing commissioned Thinking Toward Solutions and the instructors' manual that accompanies it after Saunders' representatives had a discussion about PBL with Allen at a symposium cosponsored by Saunders and the National Science Foundation.
Allen, who created most of the problems in the book, said she got ideas from her research interests and from popular science publications, such as Discover, Science Times and from the web.
Duch said that as part of the effort to expand PBL, they intend to construct a web site that will guide teachers through the process of creating these problems regardless of what they are teaching. They hope to have the first edition ready in September. "We hope to be encourage people outside the University to use PBL," Allen said.