Using "student progress" and "statistics" to prepare for class
I only taught large lecture classes a few times in my career. In these classes the lecturer seldom spends the entire hour covering new material. But the question of what else to cover is quite vexing. Paper graders seldom return written homework in less than 3 or 4 days and, generally one distributes it without trying to read it all. Thus, one never knows which have been the problems that have caused the most difficulty. One can ask the students to propose questions to go over, but often the weakest students will ask about questions that did not trouble many others. WeBWorK gives one the opportunity, within minutes of the due date (or even before) to see how all of the students have done on each problem and this provided me with wonderful guidance in more recent (admittedly smaller) classes to decide which problems to go over in class while they were still fresh in the minds of the students. I believe that it made class hours much more useful to the students.
The quickest way I found to get a snapshot of how the homework has turned out is to use the Main Menu and click on Statistics. Now one is given the opportunity to "View statistics by set". Here you can find both the percentage of the class that got correct answers and the average number of tries that it took them for each problem in the set.