Examination of J. S. Krajcik’s Theory of Science Education

Focusing on Project-Based Science

Abstract

 　This study examines J. S. Krajcik’s project-based science (PBS) theory and analyzes the outcome of his “Investigating and Questioning our World through Science and Technology (IQWST)” project.  This project sets out to make the next generation of middle school science materials.  PBS is a teaching method in science education in which children learn important scientific ideas by collaboratively engaging in meaningful investigative projects over relatively long periods.

 　In his PBS units, Krajcik identifies “learning performances” as goals that clarify scientific ideas that are appropriate for the children’s developmental stage and scientific practices that are used for mastering the scientific ideas.  Thus, in PBS, he successfully links doing science with knowing science.  Furthermore, to motivate children to engage in investigative projects, Krajcik sets driving questions that are appropriate for the children’s developmental stage and pertain to meaningful real-world problems.  In the context of learning scientific ideas through investigation, Krajcik proposes the “Investigation web,” which facilitates children understand and master scientific practices by themselves.  In an IQWST chemistry unit, Krajcik sets learning performances for each lesson, and they are structured toward the learning performance at the unit level.  Further, driving questions that correspond to each learning performance are also set.  This defines the depth of scientific ideas and practices.  Moreover, setting the performances and questions encourages children to learn scientific ideas by means of investigation, which is suggested by the “investigation web.”