1. A computer implemented method, known by those skilled in the art as authoring, wherein said authoring comprises a human author one of selecting and receiving a well-defined problem domain, said problem domain defining behavior to-be-learned by students, and an authoring system, wherein said authoring system in the preferred embodiment is known as AuthorIT, wherein AuthorIT includes a knowledge representation tool called AutoBuilder, wherein said AutoBuilder enables authors to specify to-be-learned knowledge as SLT rules in sufficient detail to enable learners in some intended student population to solve problems in a given content domain, wherein said AutoBuilder provides means for defining instruction, questions, positive feedback and corrective feedback associated with nodes in said SLT rules appropriate for learners in said student population, wherein AuthorIT includes an interface creation tool called Blackboard Editor, wherein Blackboard Editor is used by authors to define the interface for interacting with learners, wherein AuthorIT includes an Options Tool for defining the initial status of students in said student population on a Learner Model and a plurality of tutor delivery options, computer implemented authoring method comprising the steps of: a) Constructing a SLT rule for solving problems in said well-defined problem domain, wherein constructing said SLT rule consists of constructing an AST data structure and constructing a procedure AST that operates on said AST data structure, wherein said AST data structure and said corresponding procedure AST each consists of a hierarchy of nodes constructed by successive refinement, b) When a terminal node in said SLT rule is not executable on a computer, making said terminal node in said SLT rule executable on a computer, c) Assigning information, including associated media, to each node in said SLT rule, to convey corresponding instruction, question and feedback, d) Constructing at least one AST-based problem, each said problem being a data structure AST serving as data for said SLT rule, e) Assigning attributes to nodes in each said AST based problems, including at least one of location, how problem nodes are to be displayed, the kind of response learner is to provide and how learner responses are to be evaluated, all defining where and how said nodes in each said problem in the preferred embodiment are to be displayed on said Blackboard interface, f) Assigning the initial status of students in the target population on nodes in said SLT rule, wherein said SLT rule with initial status attributes in the preferred embodiment is referred to as the Learner Model, wherein the default initial status of each node is unknown to TutorIT, and g) Defining at least one set of options, using the Option Tool in the preferred embodiment to specify how TutorIT is to assign entry characteristics of the target student population, make tutorial decisions and decide when mastery goals have been attained by learners in said target student population.