This chapter provides an overview of the Personalized System of Instruction (PSI), a flexible and mastery-based model of teaching developed by Fred Keller and others in the 1960s. The key features of the model are defined and redefined, and the empirical support for the approach is reviewed. It is argued that PSI remains a compelling and attractive model for course development.
Constructivism has been embraced by many in the field of instructional design and technology (IDT), but its advocates have struggled to move beyond theory to practice or to empirically demonstrate the effectiveness of their approach. As an alternative to constructivism, a new perspective emerging in psychology, known as functional contextualism, is presented. Like constructivism, functional contextualism also rejects objectivist epistemology, but provides a much more coherent philosophical basis on which to build an empirical science of learning and instruction. The philosophical worldview known as contextualism is reviewed to outline the similarities and differences between constructivism and functional contextualism, and the key characteristics of functional contextualism and the science it supports, behavior analysis, are described. Implications of functional contextualism for research and practice in IDT are then explored.
Several prominent researchers and theorists in the field of instructional design and technology provided commentary on my article, “Constructing a Pragmatic Science of Learning and Instruction with Functional Contextualism” (Fox, 2005). Some of the important issues raised by those commentaries are addressed briefly in this reply. In particular, further clarification is provided regarding the distinction between theory and philosophy, the relation between functional contextualism and objectivism, the empirical basis and applications of relational frame theory (RFT), and the analytic goals of functional contextualism and instructional design.