2.1

What is problem-based learning?

Problem-based learning is an instructional method that teaches content and structured problem solving simultaneously through collaborative engagement with authentic “real-world” problems. PBL was developed for use in medical education in the 1970’s, and has been widely adopted in other fields including business, law, police training and even laser safety training.³ Research shows that PBL improves students’ learning and retention, motivation, critical thinking and problem-solving skills, and their ability to skillfully apply knowledge in new and novel situations – skills deemed critical for lifelong learning.^4-8 Like the similarly named project-based learning, problem-based learning focuses on open-ended questions or problems, is student centered, emphasizes inquiry, and provides authentic application of skills. Problem-based learning, however, does not require the creation of a product or a final performance, but once a problem is solved the addition of a project can lead to further learning. Since a project is not a necessary element of PBL the method may be used to solve problems in the classroom that are not practical to build in a school laboratory because of expense, complexity, time constraints or safety.⁹ In short, problem-based learning focuses mainly on the process of structured problem solving and can be independent of content. Put another way, problem-based learning teaches students “what to do when they don’t know what to do.”

Problem-based learning may take many forms, but all have some common elements:

Lecturing does not disappear entirely in PBL, but takes place on an as-needed basis as groups of students request help to understand some aspect of their independent research. The instructor’s job is to guide students in learning how to ask the right questions and to focus students’ efforts on finding information relevant to solving the problem.

2.2

The PBL Challenge Model

Problem-based learning is a major departure from traditional “end-of-chapter” problems with well-defined parameters and single solutions. During the first year of the PHOTON PBL project, the PBL team developed a format for the industry-based case studies, called Challenges, that guides students through the problem-solving process and at the same time introduces them to the types of problems common in industry and the people whose job it is to solve those problems. As with previous NEBHE NSF/ATE projects, the first step in developing PBL classroom materials was to convene a focus group of engineers, technicians, and managers from the photonics industry across New England to learn more about problem solving in an industry setting. Clearly, to become successful employees students would need to be proficient with structured problem solving, that is, a set of problem-solving techniques that can be applied to any unfamiliar and open-ended problem.

The PBL Challenges are designed to emulate the real-world context in which the problems were encountered and solved by partner organizations. Each PBL Challenge contains five main sections, each with a short video and link to section-specific resources as shown in figure 2.

Figure 2

– Main PBL Challenge Sections

The Problem Discussion and Problem Solution sections are password protected to allow instructors to control the flow of information and pace of instruction. Novice problem solvers may work together as a whole class with the instructor showing each video and allowing for discussion time after each. Students who have had some exposure to PBL may be allowed to work on the problem until they reach the point where further hints are needed, then the Problem Discussion video is shown and work continues. The most experienced students might only watch as far as the Problem Statement before engaging in long-term problem solving, perhaps followed by construction of a project. Depending on the needs of instructor and students and the time available, a PBL Challenge may be completed in as little as an hour or two (as a class discussion) or with added depth and the requirement of a tangible project it can fill an entire semester.

Finding the content for optics/photonics Challenges of PHOTON PBL was not difficult because of the large network of industry and research university contacts developed during the nine years of the PHOTON Projects. Learning how to efficiently record a problem and present it as a final product on the web required quite a bit more effort. During the development of the first few Challenges the team spent 1.5 days at the organization’s site; now the recording process takes only a few hours on location with much of the groundwork accomplished beforehand by email and phone conversations. Video production has improved tremendously as well, as excellent audio and video tools are now widely available for use by amateurs.

A Challenge begins by identifying a problem with an industry or research university partner. Suitable problems can be found through discussion with local industry or government agencies, in scientific literature and technical journals and in media resources, such as newspapers, web sites and blogs. To successfully engage students in genuine problem solving, a problem must be:

We found that a problem that has been solved by “experts” allows students to compare and contrast their solutions to the expert solution and provides a benchmark to teachers evaluating student solutions; thus, all of the PBL Projects Challenges include an “organization’s solution”.

Once a problem is agreed upon, the company is asked to provide a (preferably) diverse team of 3-4 employees for the recording session, including engineers and technicians. Each employee is asked to bring and use notebook to the session to illustrate the importance of good record-keeping. A change of clothing is also requested to illustrate the passing of time since the scenario depicted takes place over several days or weeks. The session is video-recorded to assist with script-writing and typically hundreds of photographs are taken. The actual videos used in the online Challenges are audio over still photos allowing the script to be easily altered without requiring further visits to the site.

During the recording session, the organization’s team is asked to reenact the discovery of the problem, for example, a customer makes a request for a new product or process or a production issue is discussed at a team meeting. Next, the team reenacts a brainstorming session that might have taken place a few days or weeks after the problem is discovered. Finally, the organization’s solution is recorded. Any drawings, documents or other media that will help define the problem or explain the company’s solution are requested at this time, as well as company marketing materials to use in developing a company overview video. Once the photographs are sorted and the script is written and audio-recorded by volunteer voice actors, creating the five 2-3 minute videos that will make up the Challenge is a relatively straightforward process using the iMovie application.

The NEBHE PBL Projects, PHOTON PBL (2006-2009), PBL for Sustainable Technologies: Increasing the STEM Pipeline (STEM PBL, 2009-2012) and Problem-based Learning in Advanced Manufacturing (AM-PBL, 2012-2015) have developed 20 Challenges with industry partners. These are listed in Table 1 and are available at no cost at http://www.pblprojects.org. As additional Challenges are they will be added to the PBL Projects library.

Table 1

- Topic and collaborating organization for PBL Projects multimedia PBL Challenges available at www.pblprojects.org

3.1

Student resources

The first encounter with PBL can be frustrating for both students and teachers. Students whose academic life has consisted of taking notes on lectures and completing back of chapter problems perhaps supplemented by cookbook laboratory experiments with defined outcomes can react to the open ended problems of PBL with anxiety and frustration. To help scaffold student learning of both content and structured problem solving, student resources are built into each section of a PBL Challenge and are reached via a “Resources” link in each of the five sections. Technical resources include articles and web sites with information that leads students to a possible solution to the problem without making the solution explicit. The key problem-solving resource is the “Whiteboards”, a set of instructions that guides students through a structured approach to problem solving by helping them systematically record their thoughts, ideas, and learning strategies during each stage of the problem solving process.

Figure 3

- The problem-solving cycle

The Whiteboards were developed with the assistance of the focus group of optics/photonics engineers and technicians convened early in the PHOTON PBL project to learn more about how industry approaches problem solving. Guided by the focus group discussion, we developed the Whiteboards to include four distinct steps:

The Whiteboards, shown in figure 4, derive their name from their ability to be projected onto a classroom whiteboard so that an entire class can work together, which is especially useful for novice problem solvers. They are also available to students within each PBL Challenge as a text document. Although students are usually reluctant at first to work through each step of the process and want to jump right to a solution, practice with the Whiteboards over time proves the usefulness of the method. Upon many occasions, the authors have had students return from other instructors’ classes request a copy of the Whiteboards to help them manage a complex project.

Figure 4

– The Whiteboards

3.2

Resources for teachers

A colleague once referred to Problem-based learning as “teaching without a net.” Once students have been presented with a problem and the instructor assumes the role of facilitator, the conversation can go in many unpredictable directions. For instructors used to being in control of the classroom, this situation can be unnerving. To assist faculty in implementing PBL in the classroom, the NEBHE team has developed a series teacher/faculty professional development workshops and webinars on the implementation of PBL, with workshops lasting from a few hours to several days. Resources built into each Challenge also help give instructors confidence in their ability to use the method. In addition to the technical resources available to students in each of the five Challenge sections, there is a separate “Teacher Resources” button that links to a password protected instructors’ resources site. Teacher resources include:

Figure 5

- The teacher resource page from an AM-PBL Challenge

All teachers participating in the PBL workshops are also invited to join an email listserv for discussing implementation of Challenges or sharing STEM topics of interest. The NEBHE team also posts to the listserv any changes to the PBL web site or Challenges, plus news about the project and participants.

4.1

Content knowledge

Content knowledge refers to a student’s understanding and recall of facts in a specific discipline. A test bank of multiple-choice and short answer questions, single and multiple step problems, and open ended more thought provoking problems is included in the Teacher Resources of each Challenge. These relate to the science and technology addressed by the Challenge and may be used as traditional tests, quizzes and homework. Since the PBL Challenges were designed to be implemented as either a supplemental activity in a traditional course or as a stand alone instructional method, instructors have the flexibility to assess content knowledge by traditional textbook assignments, lab reports, quizzes or tests.

4.2

Conceptual knowledge

Conceptual knowledge refers to a students’ understanding of the relationship between concepts within a subject area or between subject areas. Traditional courses often ignore assessment of concept knowledge as long as students “can do the problems.” Research on expertise shows that compared to novices, experts have a deep foundation of factual knowledge, understand facts and ideas in the context of a conceptual framework centered on core concepts and principles, and organize knowledge in ways that facilitate retrieval and application. Experts’ rich interrelated framework of concepts and principles allows them to understand and give meaning to new information by seeing patterns and relationships that are not apparent to novices, allowing them to access relevant information more efficiently. As expertise in a particular domain of knowledge increases through experience and practice, however, an individual’s conceptual framework becomes more complex and interrelated, improving their ability to transfer learning to new situations and domains^10-12.

Concept mapping has been shown to be a useful tool for assessing students’ conceptual knowledge.^13-14 Developed in the 1970s by Joseph Novak (Cornell University) as a means of assessing student conceptual knowledge in science, concept mapping provides a graphical representation of students’ understanding (or misunderstanding) of the connections between concepts in a particular subject area. A concept map consists of circles or ovals labeled with individual concepts and connected by arrows labeled with words that express the relationship between the concepts. Each pair of concepts and linking words forms a proposition that states the connection between concepts. (See figure 7.)

Figure 7

- Expert (left) and (simulated) novice concept maps for the FastCAP Challenge. Novices tend to use fewer concepts and arrange them in a linear fashion, rather than as a web of ideas.

Concept maps can be created using an “open-ended” approach with students generating their own list of concepts, or a more structured approach where the instructor providing a list of concepts to be mapped. The PBL Challenges provide a list of concepts related to the specific Challenge in order to limit variability, however, some instructors choose to have students use some of the provided concepts and also generate some of their own. Each PBL Challenge also includes an “expert” concept map for reference. A number of scoring methods have been proposed for concept mapping, some very complex requiring counting of nodes and scoring of propositions. The PBL Projects scoring rubric included with the sample concept map is based mainly on the validity of the propositions generated.

4.3

Problem-solving ability

Content assessments and concept mapping are effective ways of measuring student mastery of the subject matter of a PBL Challenge. Measuring problem solving ability involves both formative (in process) and summative (final) assessments, using the Whiteboards and a reflective journal called the Final Challenge Report. The Whiteboards are the formative assessment since as students complete them they are stating their current understanding of the problem and the thought processes that brought them to that stage. The Final Challenge Report is completed after solutions have been submitted for peer review and the organization’s solution has been revealed. Students create a detailed summary of each of the stages of problem solving as recorded in the Whiteboards, looking back at the strategies they used, what worked and what did not work, and how well their solution satisfied the company’s criteria. A final reflective exercise helps students understand what strategies will work when solving future problems.^15-17

4.4

Teamwork

One complaint by students about working in teams is that there are always a few students who are content to let others do the work, a phenomenon referred to as “social loafing”. To counter this problem, a teamwork assessment was added during the second PBL project, STEM PBL. Adapted from work by Levi and Cadiz¹⁸, the assessment is completed by students rating their teammates and themselves on a 5-point Likert scale on five measure of project-related performance:

Teamwork assessments are kept confidential and the results are counted toward each student’s grade for the project. In our experience, having teammates assess teamwork of fellow students does not completely eliminate social loafing, but the loafers are inclined to admit to their failings on their own evaluations and accept that their grade should suffer because of it.

5.1

Implementation stories

In several of regional alliances, PBL was used to bring high school and college students together, allowing high school students to experience the college environment and college students to act as mentors to young learners. For example, in 2011, students from Longview (Texas) High School worked alongside electrical engineering students at LeTourneau University to solve two STEM PBL Challenges as a supplemental after-school activity for the high school students and a graded classroom activity for college students. Alternating between high school and college campuses, The 14 participating students spent four weeks working on the PBL Challenge and then designed, built and tested their solution in the lab. More recently (2014), high school students from rural Vermont collaborated with Norwich University mechanical engineering students to solve a PBL Challenge in advanced manufacturing. According to the co-facilitating instructors, the collaboration successfully increased student engagement and encouraged deeper learning. Students gained insight into the value of PBL while working in groups of diverse ages and experience levels.

High school teachers have developed creative methods of introducing PBL into the classroom despite the demands of standardized testing. In Boston, an elective course in photonics was developed with instruction mainly through solving PBL Challenges. The teacher acted as a resource for the students but gave them little formal instruction unless they requested it. A chemistry teacher in Texas used the PHOTON PBL Challenges as a supplementary activity after the Advanced Placement test in the spring. The students knew almost nothing about optics/photonics and were able to learn a significant amount the technology as well as new problem solving strategies.

An enthusiastic Romanian practitioner of PBL introduced a Challenge to her high school class using a Socratic Seminar. Students were divided into two groups: an “inner” circle who participated in the discussion of the problem and an “outer” circle who observed the two-hour seminar and reported their observations. Students solved both the IPG Photonics Challenge (high power burn-in testing) and the PhotoMachining Challenge (laser wire stripping fine copper). After completing the Photomachining Challenge, students were eager to learn more about industrial lasers and were given the opportunity an online conversation with Dr. Ron Schaeffer, PhotoMachining CEO.

At the college level, PBL Challenges have been used both as supplemental course activities and as the basis for an entire course curriculum. One of the authors (JD) used PBL both in optics courses for students in a Laser and Fiber Optic Technology program and also in a traditional physics course to replace the first lab of the semester, “Density of a Cylinder”. In the latter case, the chosen PBL Challenge addresses the same learning outcomes as the density lab: getting to know your lab team, taking measurements and handling data in the lab. Instead of a nearly silent classroom of students measuring cylinder dimensions, the lab was alive with teams of students arguing the benefit of various community-based methods of holding back storm water. The second author (NM) uses the PBL Challenges in several courses including Introduction to Light and Lasers, a freshman physics course, and Advanced Topics in Lasers, and a senior level laser technology course. In the Advanced Topics in Lasers course, students complete three PBL Challenges over the course of a semester. The PBL Challenges serve as a foundation for many senior capstone projects and industry-based internships by introducing students to specific technology used by sponsoring companies as well as helping to develop the problem solving skills essential for success in industry. A number of other implementation stories at the college level are documented in the Implementation Stories section in each Challenge.

Figure 8

- (Left) High school students build solar shed to test ideas learned in solving the SPG Solar Challenge. (Center) College students use the Whiteboards to solve a laser safety problem in the ILDA Challenge. (Right) High School and college students work together to solve a Challenge from the STEM PBL project.

In the summer of 2013, a team of middle school teachers was engaged to develop modifications of the Challenges for differentiated instruction and assessment. Working with great enthusiasm, the team revised the Whiteboards to require student-produced diagrams, solution revision based on peer suggestions and daily “checkpoints” to align with middle school instructional methods. They also modified the Final Challenge Report and suggested additional student resources for two of the STEM PBL Challenges. One of the team members subsequently joined the AM-PBL project as a participant, and has shared his experience as a new practitioner of PBL.¹²

5.2

Student engagement

Through field-testing reports and research focus groups we have collected student and teacher responses to the PBL Challenges and methodology. While students may approach the Challenges with apprehension at first, our research has shown that with increasing exposure students gain confidence in their ability to problem-solve.¹⁹ Typical student reactions include:

Instructor reactions are positive as well:

5.3

“Make your own Challenge”

As of spring 2015, the NEBHE PBL team has presented dozens of short- and long-term professional development workshops with educators from middle school through university. Despite workshop presenters’ reminders that “it’s not about content, it’s about the method” teacher participants often remark that the content presented in the particular Challenges showcased during the workshop does not apply to the courses they teach. Teachers have requested PBL Challenges on earth and space science, environmental technology, mechanical engineering and other subject areas. During the STEM PBL project a “Create Your Own Challenge” template was developed and pilot tested with graduate-level STEM education teachers at Central Connecticut State University to teach educators how to develop PBL Challenges on topics of their own choosing and therefore increase the offerings in NEBHE’s PBL Challenge library. As a result, one of the primary goals of the current AM-PBL project is to work with participants and their local manufacturing companies to create their own Challenges.

While the online multimedia PBL Challenges developed by NEBHE have been well received in part because they capture students’ attention and efficiently present the necessary information, they are time and resource intensive to develop and maintain on the web. As a simpler alternative, the NEBHE team has created two PBL Challenge design templates available to workshop participants for creating their own PBL Challenges: the preferred format is Microsoft PowerPoint, however, acceptable Challenges can also be created in narrative form as text documents. In order have their Challenges included in the NEBHE PBL library, Challenge developers are required to use the format of the templates for uniformity.

Between 2012 and 2014, the NEBHE PBL team has been providing professional development to faculty at Kennebec Valley Community College (Maine) from two academic departments, Energy Services Technology (NSF-ATE funded) and Sustainable Agriculture and Culinary Arts, funded through the U.S. Trade Adjustment Assistance Community College and Career Training Grants Program (TAACCCT). KVCC faculty were introduced to the PBL methodology and then worked with mentors to develop their own PBL Challenges to meet the instructional needs of their programs. Several new problems have been proposed and some have reached the classroom field-testing stage. The new Challenges are based on real-world issues faced by local business and industry and they illustrate the diversity of problems that can be addressed by PBL, for example, “Under Pressure”, troubleshooting a leaky pressure release valve on a domestic hot water heater, and “Six Sick Sheep”, determining the cause of illness among ewes grazing in the college pasture.

In spring 2015, the NEBHE PBL team also worked with Trident Community College (TTC) engineering technology faculty to help them integrate PBL into their manufacturing engineering technology curriculum. As a result of the professional development provided, TTC faculty have created two PBL Challenges focused on streamlining the manufacturing flow in a craft beer factory and redesigning an accordion-type paper air filter to minimize damage during shipping.

In 2014-2015, the NEBHE PBL team has also worked closely with the U.S. Department of Labor’s YouthBuild program sites in Providence, RI, Hartford, CT, and Newark, NJ. YouthBuild provides unemployed, low-income out-of-school young people an opportunity complete their high school educations, gain the skills they need for employment, and become leaders in their communities. YouthBuild programs integrate academic skills with training in high-demand career pathways in areas such as construction, healthcare, technology, and customer service.

One of the goals of YouthBuild is to inculcate in young people the problem-solving skills needed for success on the job and in life. Working with Youthbuild represents a slight departure for the NEBHE PBL team from its focus on STEM education to providing more generic problem solving skills to a different population. Over the past year, NEBHE PBL mentors have worked closely with YouthBuild teachers and counselors to modify their existing curricula to incorporate real-world problem solving experiences and tools (the Whiteboards) into their daily activities. Although each of the Youthbuild sites has experience with student projects, the goal of the NEBHE partnership is to help faculty find the problems embedded within the projects and give students the skills to solve them.

Reactions from both teachers have been extremely positive:

6.1

From projects to problems with new populations of students

The NEBHE PBL team is frequently asked “What’s the difference between project-based learning and problem-based learning?” Both are learner-centered approaches to education that fall under the broad umbrella of inquiry-based learning. Both PBLs focus on open-ended problems or tasks and provide authentic applications of skills and content knowledge. But while project-based learning requires the development of an end product developed according to some specifications, problem-based learning is more focused on the process of problem solving. In fact, problem-based learning can be thought of as the “front end” of the process, where the problem is identified and researched and solutions are proposed. That is, problem-based learning generates the criteria for project design. (See figure 9)

Figure 9

- The Problem-Project based learning continuum

Figure 9

– Industry sponsored senior capstone projects

Many educators who have attended NEBHE PBL professional development workshops have already been using hands-on projects to engage students but are now looking to take the next step to turn projects into problems integrating key 21^st century skills: problem solving, critical thinking and teamwork. For example, at the time of our initial contact with the Newark, NJ YouthBuild site, the teachers were planning a project to build raised bed gardens to be located on school property. Teachers and staff had worked with an outside consultant to develop plans for students to implement. Converting the project to problem-based learning, teachers broke the large project into a series of smaller ill-structured problems requiring students to use the methodology of PBL to identify the problem and research and propose solutions.

In addition to providing an exciting educational alternative for special populations such as the overage/under credit students of Youthbuild, PBL also meets the new demands of the Common Core and Next Generation Science Standards for teaching critical thinking and problem solving as well as interdisciplinary studies, teamwork and engineering practice. Through the success, dissemination and credibility of the three PBL Projects’ instructional materials and professional development model interest and demand from K-12 schools and colleges who are searching for PBL training services has grown. The PBL team is working to develop a model of structured problem-solving tools that can be customized to specific populations such as young elementary or middle school children.

6.2

Case Study: Internships and capstone projects

The NEBHE PBL team constantly asks itself “How do we improve on what we are doing now to help students further develop the real-world problem-solving skills needed by industry?” Applying our own problem solving strategies to answer this question, one of the solutions was to make the experiences provided by the PBL Challenges even more “real.” To this end, one of the authors (NM) set out to develop student internship and capstone project experiences with some of the companies that sponsored the PBL Challenges, and companies involved in similar industry applications. The idea is that students who have completed several PBL challenges have already been exposed to the company, the problems they routinely face, their process for solving those problems, and would be able to “hit the ground running” in applying what they have learned in an actual real-world setting.

Over the past five years, dozens of senior students in the Laser Electro-Optics Technology program at Springfield Technical Community College have participated in onsite internships as part of their two-semester senior capstone projects at several local photonics companies. The projects selected by these companies were real engineering projects in which the students served as an integral part of an engineering team. A list and photos of a few selected projects is provided below in table 2 and figure 10.

Table 2.

– Partial list of industry sponsored internship projects

While anecdotal, the response from both students and industry partners has been exceedingly positive as evidenced by the hiring of student interns by sponsoring companies upon graduation. For example, in 2014, Nufern Inc. sponsored nine senior projects and hired all nine student interns. Similar hiring has occurred with all of the other sponsoring companies with extremely positive feedback. Moving forward, we intend to expand student capstone project internships with additional PBL Challenge partners and conduct research on the impact of PBL on initial job performance of PBL graduates as compared to non-PBL graduates.