The system will generate multiples of a report card for a single student when that student has more than one address marked as a mailing address in Core. In order to generate a single report card, one of the mailing addresses must be removed. 

To do so: 
  1. Navigate to Core > Users > Edit user profile data
  2. Search for and select the student 
  3. Under Address in his or her profile, click Edit for the address you wish to remove as a mailing address
  4. Unmark the Mailing Address checkbox
  5. Click Save & Exit