To work with sets and grouping use the Reordering Control (4) on the Test or Section
Reordering, Grouping, and Randomization
Learn about the four ways to randomize the way your online exam is delivered to test takers.
The concept of an OWL "set" is important because it is the way OWL offers its users so much flexibility in the way they present their online activities. It appears in several places including points, randomization and reporting. Watch this quick video for an explanation.