"Problem-based learning (PBL) is a student-centered pedagogy in which students learn about a subject through the experience of solving an open-ended problem. Students learn both thinking strategies and domain knowledge. The PBL format originated from the medical school of thought, and is now used in other schools of thought too. It was developed at the McMaster University Medical School in Canada in the 1960s and has since spread around the world. The goals of PBL are to help students develop flexible knowledge, effective problem solving skills, self-directed learning, effective collaboration skills and intrinsic motivation. Problem-based learning is a style of active learning.
Working in groups, students identify what they already know, what they need to know, and how and where to access new information that may lead to the resolution of the problem. The role of the instructor (known as the tutor in PBL) is to facilitate learning by supporting, guiding, and monitoring the learning process. The tutor must build students' confidence to take on the problem, and encourage the students, while also stretching their understanding. PBL represents a paradigm shift from traditional teaching and learning philosophy, which is more often lecture-based. The constructs for teaching PBL are very different from traditional classroom/lecture teaching."
[Source: "Problem-Based Learning". Wikipedia. https://en.wikipedia.org/wiki/Problem-based_learning]
Problem-Based Learning typically follows prescribed steps:
Problem-based learning is very similar to project-based learning. Both use inquiry and a student-directed approach and both use the same abbreviation of PBL. But the two are slightly different!
For a summary of each approach and highlights of the similarities and differences between problem-based learning and project-based learning, read this blog posting by John Larmer, the Editor in Chief of the Buck Institute for Education. In the post, Mr. Larmer states that: "We [Buck Institute for Education] decided to call Problem Based Learning a subset of Project Based Learning; that is, one of the ways a teacher could frame a project is 'to solve a problem.' But Problem-BL does have its own history and set of typically-followed procedures, which are more formally observed than in other types of projects... the semantics aren't worth worrying about, at least not for very long. The two PBLs are really two sides of the same coin. What type of PBL you decide to call your, er . . .extended learning experience just depends on how you frame it. The bottom line is the same: both PBLs can powerfully engage and effectively teach your students!" [emphasis added in bold font]
SOLEs (Self-Organizing Learning Environments) are another flavor of Project-Based Learning. For more information, read this article Messy Works: How to Apply Self-Organized Learning in the Classroom by Katrina Schwartz.
Another flavor of Project-Based Learning is Solution Fluency which is the ability to think and solve problems in real time. For more info, read this Solution Fluency Quickstart Guide from Global Digital Citizen Foundation. Note the rubric on page 13.