This is stupid! Why do we need to know this?" How often have we heard these phrases in our middle-level classrooms? After years of struggling with the 8th grade phenomenon of "Anything that is not directly applicable to my life is useless and therefore stupid," we began our trek down the path toward Problem-Based Learning (PBL).
Problem-Based Learning is the epitome of constructivism. Students receive a real or a potentially real problem and devise a practical solution from the research that they do. We design problems so that students learn a variety of skills as well as meet curriculum objectives.
A PBL classroom looks different from a traditional teacher-centered classroom because student activity is the norm. Whether gathering information or drawing conclusions, students work in groups, confer with others, do labs, create physical displays, or consult resources outside the classroom.
When in full swing, our class has any number of students at the media center; in the tech lab; on the phone with outside contacts; and sprawled in the hall discussing, questioning, brainstorming, and creating. Though it is an exhausting process, we are equally exhilarated to see 55 to 60 eighth graders so engaged in thinking!
From Lake Michigan to China
What are these students engaged in? We work hard to design problems that not only teach the curriculum but also interest most 8th graders. Our best problems are intentionally open-ended. For instance, we had our students design a mass transit system to run from Chicago to Michigan City, Indiana, over, under, or through 57 miles of Lake Michigan. They loved the assignment! Part of the intrigue was that it hadn't been done (some experts told our students that it couldn't be done). The task challenged both their imagination and their intellect. Their working models were not only creative but also scientifically accurate. One notable model was a "bank teller" pneumatic tube that moved 50 passengers through the 57 miles in less than seven minutes with a force less than 1/3 g. By creating a vacuum, which they demonstrated during the presentation with a Shop-Vac, the students accomplished their goal in a way that was mathematically supported and monetarily feasible.
We also asked students to design a car for the growing needs of China. Students had to understand not only how a car works, but also the political and economic realities in China. This problem incorporated all subject areas. We applied constraints to the product as well; students had to use an environmentally friendly fuel source and materials that were readily available in China. Once students realized that a traditional internal combustion engine was out, the fun began. One group used rechargeable batteries, another used solar power, and a third used a methane source.
Environmental Solutions
Another hook to get students engaged in their learning is to let them make a difference in their natural world. One successful problem asked students what to do about an island estuary for great blue herons and great egrets. The island, located in a lake near the school, was vegetatively dead, and students had to find a way to keep the birds from leaving the island and finding a new nesting ground.
Although this complex problem involved not only intricate ecosystems but also local politics, students rose to the challenge when they presented informed solutions to a panel of adult experts. One group wanted to drain the lake and bring in fresh soil and new vegetation; another wanted to let nature take its course. Yet another found that crayfish could digest the increasing load of bird waste and suggested that they fill the lake with crayfish.
Although each solution was unique, all groups supported their conclusions with facts from in-depth research. To aid in their presentation, students constructed models of their island. Some used modeling clay and plastic birds; others used Popsicle sticks and tempera paint; still others used actual twigs and peat moss. They constructed models during class periods so that we could coach all group members and make sure that everyone participated equally.
Each year, students examine an environmental problem within our community, such as heron rookeries, prairie restoration, or stream bank stabilization. Because these problems are current and local, no books or magazine articles have been written specifically on them. Therefore, students have to find resources and construct meaningful scenarios on their own.
Whether their performance assessment involves a presentation to a panel, a pamphlet for community distribution, or a letter to the school board, the students impress experts with their ability to synthesize information. The moral of this story: Trust that your students will do good things, and put them in a position where they have to show off. They will usually meet and exceed your expectations.
Coaching and Modeling
We start with a well-designed problem—one that students buy into—and turn them loose. But how do we ensure that this bunch of thinkers actually goes in the direction that we intend? How do we make sure that they learn what they need to know? Most important, how do we know that students are actually thinking and not just information-munching? That's where the fine art of coaching comes in.
We know that 8th graders are pretty good at fact-finding. But when given questions on a worksheet, they find the easiest answers and believe that they are finished. A PBL teacher as coach gets students to think on a higher level to use crucial critical-thinking skills, such as evaluation and analysis. We ask questions like, "Why do you think this information is important to the problem?" and "What conclusions can you draw now?" When students look deeper and ask more questions, they learn to search out relationships between pieces of information and come to expect that we always want more. The question then becomes, How can we be sure that they are asking the right questions? The answer is even tougher: modeling.
The first thing that we do after introducing each problem is to discuss what students know about the topic to determine what they need to know. Even at this stage, as students shout out information, we continually ask, "Why do you think this is important?" or "Can you tell me more about that?" Once students hear these questions enough, they begin to ask the same questions when they break into groups. By the second or third problem, students spend group time probing one another's knowledge and challenging one another to look deeper and keep questioning.
With all this probing, do students really ever learn anything? What we know from current brain research is that we form more lasting memories when the new subject connects in some way to old, familiar memories. Because the root of every problem springs from students' prior knowledge and proceeds logically, students internalize the new information to a greater extent. We also know that activities or ideas that elicit strong emotion—disgust, excitement, or accomplishment, for example—tend to form more lasting memories. If the problem is good—and innately interesting—the emotions take care of themselves.
Authentic Evaluations
How do we evaluate this depth of learning? Throw away those No. 2 pencils because Scantron just won't cut it. Because our PBL class is a fully integrated science and language arts class, our evaluations often call for presentations, both oral and written, as well as physical projects. Scale models of the transit systems, audiovisual aids for presentations, full-color ad campaigns, photo albums of the solution process, even an interactive museum display are a few examples. Students are never able to slide by with just fact-regurgitation but have to show their knowledge in multiple ways.
We score projects and presentations on precise rubrics with stated curricular objectives so that students know ahead of time what we expect of them (see fig. 1). Because we assess student work in a variety of modalities, students who are not strong in one area have the opportunity to excel in other areas and can succeed overall. We never assess students on "right or wrong" answers, but on whether their conclusions are based on accurate facts and are logical and supportable.
Figure 1. Car Project Requirements
Goal: To create a car from simple objects that will exceed the speed or acceleration of any other car. Your vehicle should approximate the exterior shape of your actual car.
Rules:
You may use only the items specified below.
All cars must be self-propelled.
All calculations must be done neatly.
You do not have to use all the items in your bag.
Any cars with extra items will not get higher than a 70 percent.
Items supplied to you or that you may bring from home:
1 paper-towel roll
1 roll bathroom tissue
8 paper clips
2 rubber bands
2 straws
2 plastic sticks
1 lunch baggie
1 grocery bag
2 m (max) tape
Elmer's Glue (unlimited)
1 sheet paper
1 cardboard egg carton
bottle caps (wheels)
scissors for construction
coins (for weights)
Calculations required:
mass
speed
acceleration
distance traveled
power
work done by car
momentum
Information to be included in your written proposal:
Name of your vehicle
Approximate cost
Interior and exterior dimensions
Type of engine and dimensions
Expected efficiency of your vehicle
Fuel source and reasons for this fuel source
What the interior will look like and include
Why your proposal is best
In our Lake Michigan transportation problem, one group came up with a system similar to a ski lift with gondolas suspended for 57 miles over Lake Michigan. The moment that this group completed its presentation, other students questioned the feasibility of the system. Because other groups had done such quality research, they were able to ask good questions and judge the accuracy of the answers. By the end of the project, we became a community of analysts assessing one another's problem-solving skills!
Although most work in Problem-Based Learning is done in small groups, we determine individual grades through journals, learning logs, and other work. Because we are in constant communication with each student throughout the problem, we know how much each student participates and can determine his or her level of understanding.
Celebrating Success
After students have reached solutions, teachers and students meet together in a large group to debrief the problem. During this time, we coach students to look at what they did well, what caused them difficulties and why, and what they would do differently next time. We ask them to celebrate what other groups did well, which in turn helps them learn new strategies. This process gives teachers and students an opportunity to see growth over time. As students get better at the process of creative problem solving, their debriefings become more sophisticated.
To see real growth in students' critical-thinking skills, teachers should use PBL as the organizing strategy in the classroom—not as a one-shot strategy. In addition, we suggest training for teachers before they implement PBL because the skills that make good PBL teachers are not necessarily those used in other classroom contexts.
Problem-Based Learning is an exciting way to help students construct their own knowledge of problems. Through teacher coaching, students learn knowledge that applies to their real lives and are therefore more willing to learn. Because the information comes in the form of an interesting problem, PBL is more engaging to students, and because students construct knowledge logically, they retain the information. For middle-level students caught up in the "blahs" of traditional school, no method better develops thinking and motivated students than PBL.
