I've created a SOQL script connected to the School object and it runs fine with these criteria -SELECT Name, Country__c, School_Id__c, Teachers__c FROM School__c ORDER BY Country__c ASC

But, when I add other additional criteria from the object i.e. District__c : SELECT Name, Country__c, School_Id__c, Teachers__c, District__c FROM School__c ORDER BY Country__c ASC
I get the following error message: 
INVALID_FIELD    Country__c, School_Id__c, Teachers__c, District__c
                                       ^
ERROR at Row:1:Column:53
No such column 'District__c' on entity 'School__c'. If you are attempting to use a custom field, be sure to append the '__c' after the custom field name. Please reference your WSDL or the describe call for the appropriate names.    Global School Name Query 8 All Schools Info.soql

Does this mean the field District_c is on another object? Thanks for any help.