Flagging key concepts is strictly a communications tool and has no other impact on the behavior or scoring of the Personal Study Plan.
Open the My Classes page.
Click Classes › My Classes and find the section you want.
Click the Personal Study Plan tab.
Click Settings.
The Personal Study Plan settings window is displayed.
Select the Flag Key Concepts check box.
Expand a chapter with sections that you want to flag by clicking
.Click the flag icon
for a section to change its status.Flag Color
Status

The section is not a key concept.

The section is a key concept.
Click Save.