Abstract
In self-learning, most of the learners improve gradually their understanding through trial-and-error learning process. It is difficult for the traditional frame type CAL (Computer Assisted Learning) to assist a learner in his trial-and-error learning due to lack of its assisting ability. In this paper, the authors design the trial-and-error learning model for a frame type CAL with fuzzy grades of learner's understanding in fuzzy set theory. Our CAL model fulfils successful assist in trial-and-error learning.