Hi Sandra: Great summary of one purpose of pretesting. Another version some teachers use is when they want to compare the accuracy of teacher rating students. For instance, how likely is it that say, 5 different teachers were to ask the same questions of a class, how close would their assessments be. This is called inter-rater reliability, and using a pretesting model is often how that is accomplished. More commonly, pretesting helps the teacher plan tweaks in their curriculum to better suit their current students. Regards, Barry