Guest Editors' Introduction: Intelligent Educational Systems of the Present and Future

Education in the 21st century faces an increasing number of challenges that require intelligent systems. The learning environments of today and tomorrow must handle distributed and dynamically changing content, a geographical dispersion of students and teachers, and generations of learners who spend hours a day interacting with multimillion-dollar multimedia environments. The new learning environments are moving beyond kindergarten through college classrooms to distance learning, lifelong education, and on-the-job training; they're entering the multifaceted universe of virtual worlds and ambient spaces. The articles in this special issue report novel, cutting-edge, intelligent learning environments. The systems not only have intelligent computational architectures but also are empirically tested on humans. Empirical research is of course essential to test system fidelity in delivering the intended pedagogy and to assess learning gains, usability, and learner satisfaction. This article is part of a special issue on intelligent educational systems.