This month, I discuss how PBL differs from other forms of learning and provide an example. The primary distinction is that PBL uses the challenge of solving real world problems to introduce curriculum concepts and motivate and focus student learning. Therefore, a critical factor in the application of PBL is the problem itself.

Characteristics of good PBL problems

1. An effective problem must first engage students’ interest and motivate them to probe for deeper understanding of the concepts being introduced. It relates to the reality of the student’s world and interests.
2. Good problems induce students to make decisions or judgments based on facts, information, logic and/or rationalization. They require students to justify decisions and reasoning based on the principles being learned.
3. Cooperation from all members of the group is necessary in order to effectively work through a good problem. The length and complexity of the problem is such that students realize that a “divide and conquer” effort will not solve the problem. For example, a series of “end of chapter” type questions would likely end up being divided by the group, assigned to individuals, and reassembled for a solution, in which case students gain little critical thinking and problem solving experience.
4. The initial questions in the problem have one or more of the following characteristics so that all students in the group are initially drawn into a discussion of the topic:
1. open ended, not limited to one correct answer
2. connected to previous learning
3. controversial issues that will elicit diverse opinions.
These characteristics keep the students functioning as a group, drawing on each other’s knowledge and ideas rather than encouraging them to work individually at the onset of the problem.
5. The objectives and standards of the curriculum are incorporated into the problem. The problem also connects to concepts in other curriculum areas.

Higher order thinking skills

In addition to these characteristics, good problems challenge students to not only use, but go beyond factual information to a deeper understanding of the subject. Too often, students view learning as remembering facts, terms and definitions in order to answer questions on tests.

Remember Bloom’s Taxonomy of Educational Objectives? Bloom matches cognitive levels with parallel student activities, and arranges them from simple to complex.

Good PBL problems induce students to operate at the higher Bloom levels where they

analyze, synthesize and evaluate rather than simply define and explain.

Marion Brady, in an article entitled Teaching Students to Think published in the February 2008 issue of Education Leadership, writes, “A focus on real-world issues can alter the entire culture of a school or school system. It enables students and teachers to experience the "meatiness" of the direct study of reality. It's unfailingly relevant. It shows respect for students, who become more than mere candidates for the next higher grade… and it shifts the emphasis from cover-the-material memory work to a full range of thinking skills.”

Where to find good problems

So now that we know what makes a good problem for use in PBL, where can you find ones that relate to the subject you teach? Some teachers make up their own PBL problems. Others pick up on stories in the media or rewrite an end-of-chapter textbook question as an open-ended real world problem. Two recent publications by Prufrock Press (www.prufrock.com) coach both teachers and students, grade 3 - 12, on using the Internet to solved PBL problems. The books present several real-life problem scenarios along with teaching notes and reproducibles.

Here is an example of a real-world PBL problem for a math, civics, physics, or even a driver education class.

The city parking commission is considering changing the parking on Main Street in order to increase the number of vehicles that can park in the available space. Cars now parallel-park like so:

The parking commission is proposing several alternatives. One of their solutions is to require vehicles to angle-park. They are concerned, however, that cars backing out of angled parking spaces will be apt to collide with vehicles driving by because visibility will be blocked by the cars parked next to them. One of the commissioners proposed that instead of nosing into an angled parking space, drivers back in, thusly:

The parking commission has asked the class to study the maverick commissioner’s suggestion and give its opinion of the idea. They would like to know whether it is better than traditional, nose in angle-parking. Why or why not. What about safety issues, the environment and aesthetics? What about public acceptance and law-enforcement concerns? Is this a brilliantly conceived solution to the problem, or is it the most lame-brained scheme of the century? Even though the class isn’t asked to do so, can we offer other ways to increase available parking space that have not been considered?

In next month’s Gazette, I will suggest ways to organize and structure a class to get the most out of PBL.

(Editor's Note: Here's a 7:28 minute video tutorial on writing a good problem statement ("driving question") teachers.net/gazette/APR08/video/#prob

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