PSLC thrusts carry specific goals and research questions that cohere around the research goals of the center. We have promoted more explicit integration through a center-wide group effort of theory building. The results of this effort are the development of a core learning and instruction vocabulary and in broadly shared framing of learning hypotheses and instructional principles. These core vocabularies and common framings can be seen on the PSLC wiki, in published papers and in the description of thrust research, which is described in the following sections. PSLCs key conceptual vocabulary includes knowledge component, feature validity, refinement, learning event, learning event space, etc. This shared vocabulary supports real connections across projects whose studies involve instructional manipulations such as feature focusing, scheduling, or self-explanation in different ways in different domains.Each of the four thrusts has an associated key research question:
1.Cognitive Factors. How do instructional events affect learning activities and thus the outcomes of learning?
2.Metacognition & Motivation. What learner factors mediate whether instructional events produce desired learning events?
3.Social Communication. How can social communicative patterns be structured in classrooms to enhance robust learning?
4.Computational Modeling & Data Mining. How can student interaction data and discovery algorithms be used to develop precise models of knowledge, learning and instruction?