uiry learning?
This is a great question, and a difficult one! These practices share a lot of characteristics, but also have many nuanced differences. I'll do my best to tease out those distinctions here.
The most important thing about these three models of instruction is what they share: they all put students in a leadership role in pursuing learning, and they all require students to grapple with challenges and formulate ideas or solutions. As for what distinguishes each model, there is not a simple answer. Definitions for each model vary and the models overlap in many ways. While proponents for any particular model tend to use tight definitions to describe it, as a whole the terms are often used loosely--and even interchangeably--in general educational settings.
Inquiry learning is the broadest term and project- and problem-based learning are both subsets. Inquiry learning includes all instructional strategies that compel students to explore materials and concepts. This approach is found, for example, in the pre-school model of the Reggio Emilia Schools; in the elementary school technique of Guided Discovery, framed by the Responsive Classroom model; by the Montessori model; and by a wide range of art and science programs that use discovery and experimentation to encourage students to develop ideas, techniques, and hypotheses. Discrete practices such as Socratic Seminars that involve students in leading inquiry-based discussions are also often seen as part of inquiry learning. You can see high school students leading an inquiry-based discussion protocol very capably here.
Problem-based and Project-based learning are terms that are often used interchangeably. There is not universal agreement on how they may be distinct, but those who distinguish them tend to cite these differences:
- Real World Connection
- Project-based learning is typically used for real world-connected projects for authentic audiences (e.g., students interview local civil rights heroes and publish a book to honor their stories; students create a water quality report for the town about a local stream)
- Problem-based learning may use simulation problems or academic problems that are challenging provocations to thinking but may not have real-world use (e.g., design a container with flat surfaces and minimal surface area to hold a set of given objects; describe a fair solution to an ethical dilemma from history)
- Disciplinary versus Interdisciplinary
- Project-based learning is often deeply interdisciplinary; the real-world connection typically involves research, design, creation, and communication
- Problem-based learning may be primarily centered in a single discipline (e.g., inquiry-based math lessons often include problem-based learning)
- A Final Product or Performance
- Project-based learning typically results in a final draft product or performance that is shared with the public (e.g., book, machine, display, blueprint, website, symposium)
- Problem-based learning may culminate in a solution, but is not necessarily brought to a polished product
The Case Study approach--best known from its use in medical schools, law schools, and business schools--is one particular branch of problem-based learning that is highly-defined and sometimes prescribed in its pedagogical steps. That approach has inspired and informed use in undergraduate and K-12 classrooms as well.
All of these models of instruction, when used well, can build student ownership and engagement and push student thinking in ways that are difficult to match with other pedagogical approaches. Some of that power is self-evident when viewing high-quality student projects. If you're interested in seeing examples, I encourage you to visit the Center for Student Work. For the past 25 years, I have been working with my colleagues at Expeditionary Learning and at the Harvard Graduate School of Education to build and curate an archive of exemplary student projects, which are now housed online in this center.
At the center, you can view projects like this one, in which seventh-grade students at Polaris