I have explored the instructional value of using multiple-possibility problems (MPPs) in introductory physics courses. MPPs are different from regular problems most often encountered in textbooks since 1) they have missing information, vaguely defined goals or unstated constrains, 2) they possess multiple solutions with multiple criteria for evaluating the solutions, 3) they present uncertainty about which concepts, rules, and principles are necessary for the solution or how they are organized.

Real-life problems and professional problems are MPPs. Students rarely encounter such problems in introductory physics courses.

Kitchener proposed a three-level model of cognitive processing to categorize the thinking steps one makes when faced with such problems (cognition, metacognition, epistemic cognition). The critical and distinctive component of MPP solving is epistemic cognition (EC). At that level individuals reflect on the limits of knowing, the certainty of knowing, the underlying assumptions made. It is an important part of thinking in real life.

Firstly, I developed and tested a coding scheme for measuring EC. Using the coding scheme I compared the EC level of experts and novices by conducting think-aloud problem-solving interviews with them. Although experts had higher EC level than novices, in some instances a novice showed an expert-like EC. I found that prompting question during interviews were 50% effective for students.

Secondly, I tested two hypotheses by conducting investigations in an algebra-based physics course: 1) Solving MPPs enhances students' EC; 2) Solving MPPs engages students in more meaningful problem solving and thus helps them construct a better conceptual understanding of physics.

I found supporting evidence for both hypotheses. Although not all results unquestionably support the hypotheses strongly, they show much promise for MPP use in introductory physics courses. I also created a bank of MPPs freely available for use.