A tailored testing model employing the beta distribution, whose mean equals the difficulty of an item and whose variance is approximately equal to the sampling variance of the item difficulty, and employing conditional item difficulties, is proposed. (Author)

Examines the importance of levels of questioning and types of feedback in designing courseware for computer-based education. Test results are analyzed for four groups of high school students who completed different versions of a computer-based science lesson, and recommendations for future research are given. (Author/LRW)