Group members - and admins - are by default listed in alphabetical order by last name on the "Members" tab, however, teachers and Site Administrators can change the order in which admins are listed in the class page header, however.
By default, group admins are listed alphabetically in the header. To change the order, click the "Edit Members" link in the "Members" section.
A Group Manager window will pop up. In this window, admins will have a "Position" column field that regular group members don't have. Enter a number into each group admin's Position column. Group admins will be listed in numerical order based on the contents of the "Position" column, with the lowest number at the top. Make sure to save once you have ordered your admins.
The option to make someone a "Hidden" admin will appear for those listed as admins in the members list. This checkbox will allow the individual to have full admin rights but will not appear in the list of admins for the group space. Find out how hidden admins can access their group spaces.