So here's a query I keep around as a generic "tell me the group" query. I am not a huge SQL person, so this could be messier or more resource intensive than it should be. I don't know and I run against test databases which have few nodes.
Right-click on your AD Organizational View, choose Properties, and record the GUID. Then insert it into this query as directed below. No {} marks, just single quotes around the value.
Then right-click the 'Schools' OU and record this GUID, inserting it as directed below for the ParentFolderGuid value. This will then return the GroupName for a computer's group if the computer's parent group is the OG synchronized with the AD OU 'Schools' and the OV is the AD synchronized view.
This only goes one level below, so this should tell you the numerical school value. As an example, if you ran this against the Default view, and gave the GUID of the 'Network Resource' OG, you would only receive computers in the group 'Computer,' but not computers in the group 'Virtual Machines.'
SELECT
v1.[Name] as 'ComputerName',
Item.Name as 'GroupName',
Item.Description as 'GroupDescription',
v1.Guid as 'ComputerGuid',
ScopeMembership.ScopeCollectionGuid as 'GroupGuid',
Item.SecurityGuid,
ScopeCollection.ScopeSetGuid,
ScopeCollection.ScopeCollectionGuid,
ScopeMembership.ResourceGuid,
ScopeMembership.ScopeCollectionGuid
FROM
vComputer v1
JOIN ScopeMembership ON v1.Guid=ScopeMembership.ResourceGuid
JOIN ScopeCollection ON ScopeMembership.ScopeCollectionGuid=ScopeCollection.ScopeCollectionGuid
JOIN Item ON ScopeMembership.ScopeCollectionGuid=Item.SecurityGuid
JOIN vItemParentFolder ON vItemParentFolder.ChildItemGuid=ScopeMembership.ScopeCollectionGuid
--Return results only if the Organizational View is the Active Directory Organizational View
WHERE (ScopeCollection.ScopeSetGuid='GUID OF ACTIVE DIRECTORY VIEW' AND vItemParentFolder.ParentFolderGuid='GUID OF THE ORGANIZATIONAL GROUP CALLED SCHOOLS AND SYNCHRONIZED WITH ACTIVE DIRECTORY')