This document outlines the operation of the Monte Carlo Integration Computer (MCIC), which is capable of simulating several types of chemical processes. Some data obtained through the MCIC simulation of physical processes are presented in graphs. After giving reasons for not using the initially contemplated summative research procedures for evaluation of the MCIC as a teaching aid, the author chooses to use a diagnostic or formative evaluation. Evaluation occurred over three lecture/demonstrations of the MCIC to high school chemistry students in Philadelphia. Sample findings from one problem area - understanding the presentation of the MCIC - were presented to illustrate that formative evaluation of instructional materials might be more profitable than more traditional evaluations. (JM)