What's the difference?

Case based learning has a defined context that engages students in conducting activities to come up with viable solutions to the problem(s) posed in the case. A case study may include data (graphs, figures, tables) and assumptions and it approximates a possible real-world scenario. The scope of a case varies depending on the course objectives and related course competencies that an instructor wants students to achieve or it can be based on student learning outcomes attained through the case-based activities, or both.

The scope of the problem outlined in a case may expect students to demonstrate only their ability to apply tools, techniques, knowledge and skills to the possible solutions, or the case scenario may be comprehensive in its requirements to demonstrate additional student outcomes that include methodology constraints, ability to work effectively in teams, ability to communicate effectively through technical reports and presentations, analyze the impact of their solution in societal, environmental and global setting and the like.

Engineering has a very definite view of what constitutes a project. In the framework of project-based learning, I find it hard to sharply distinguish project-based learning from problem-based learning. My professional experience and takeaway from the readings is that the two differ in course objectives and student learning outcomes.

Outcomes in project-based learning are more focused on application of knowledge

        

Outcomes in project-based learning are more focused on application of knowledge, tools, techniques and skills to achieve the objectives of a project, versus problem-based learning where students articulate gaps in their knowledge and implement ways to fill those gaps by acquiring knowledge followed by potential application of the newly acquired knowledge in the context of the problem.

Outcomes in problem-based learning are more focused on acquisition of knowledge
        

Both problem-based learning and project-based learning are similar in that the learning activities focus on broadly defined engineering and engineering technology problems that may involve wide ranging or conflicting technical issues, involving diverse groups of stakeholders, having no obvious solution, addressing problems not encompassed by current industry standards, including many sub-problems, requiring a multidisciplinary team approach, or having significant consequences in a range of contexts.

Both can have explicit or implied constraints such as physical design specifications, operational, economic, environmental, social, regulatory, political, ethical, health and safety, reliability, maintainability, producibility, supportability, sustainability, disposability and several other elements of logistics and support considerations.

Problem-based learning can be rigorously iterative (like Systems Engineering), as opposed to project-based learning where the criteria for project success is well-defined within a solution space. If it falls outside the solution space, its is considered a failure, lessons learned are documented and incorporated into the revision.

Project-based approach also emphasizes extensive planning before execution and incorporates rigorous controls to ensure no deviation occurs from the baseline. Problem-based learning is focused on revealing new insights and knowledge and implementing those into the solution on a rolling basis, incorporating the need to engage in life-long learning and ability to acquire and apply new knowledge as needed, using appropriate learning strategies and articulate what has been learned.

Problem-based learning is not very suitable for teaching technical courses that require application of knowledge, tools, techniques and skills. Problem-based learning can be implemented in an engineering pre-capstone degree project with well structured requirements, but a very vaguely defined problem. This approach can help team of students in acquisition of knowledge that will later be applied in implementing the project design.