You may want to temporarily deactivate and archive a group without deleting it. You can do this on the group's main page. When you deactivate a group, all attendance history for the group is hidden on the Attendance Dashboard, the Attendance Profiles, and the group history on the individual's profile page. Inactive groups can be included in reports. However, once deactivated, groups will not display in queries or on the dashboard.
and select Deactivate Group.