It is possible to create a User Defined Group in Sims and use this group to report in Discover. For Example, it may be that you wish to report on Whole School attendance in Discover but that you want to exclude Nursery children. For help on creating a User Defined Group please see FAQ:
In order for the group to appear in Discover, you will need to tick the box “Include in Discover”
To access this group in Discover, click on the “Pastoral” catalogue button and then select “Student Totals by User Defined Group”
From here, drag and drop the “Student Totals by User Defined Group” on to the blank screen.