You can edit the Study Plan and set the default mastery criteria. This property is on the Study Plan Properties page. (Show me the property.)
For Mastery Criteria, specify whether the MyLab should base mastery of a topic on a student's most recent score or highest score in a set.
Students do not need to work through all exercise sets to achieve mastery. A student can achieve mastery based on a diagnostic pre-test or a topic's exercise set(s).
See also:
Edit Study Plan Properties | Customize the Study Plan