Intelligent tutors for all: Constraint-based modeling methodology, systems and authoring
Intelligent Tutoring Systems (ITS) have revolutionized online education by providing individualized instruction tailored towards each student. Constraint-based tutors model instructional domains at an abstract level, a novel approach that simplifies the development of ITSs. We have developed many effective constraint-based tutors over the last decade in a number of instructional domains of various characteristics, some of which have been successfully commercialized. Constraint-based tutoring is now a mature and successful approach to providing adaptive learning environments. Our authoring tools aim to make this technology widely available to teachers and students everywhere.