This paper explores the realm of evaluation within the domain of Intelligent Tutoring Systems (ITS). Toward that end, Littman and Soloway (1988) described two facets of evaluation: external and internal. Described here are a variety of procedures that they did not address and some that they discounted. One of the procedures not explored was the use of Bloom's (1984) "2-Sigma Problem." Anderson, Boyle, and Reiser (1985) used this procedure to externally evaluate the Lisp Tutor. Priest and Young (1988) offered a variety of procedures that can be used for internal evaluation. These procedures are presented and POSIT (an ITS for subtraction of whole numbers) is used as an example case to illustrate the evaluation procedures. (26 references) (Author/BBM)