You will want to change the Class Of in The Education Edge first, then perform the following steps:
  1. Go to Core > People Finder
  2. Select the Student
  3. Select the Access tab
  4. Click the Pencil icon next to Student and select Edit School Enrollment
  5. Click Add another enrollment
  6. Enter information for the Current Year
  7. Adjust grade level(s) as needed for future years
  8. Delete any unneeded years
  9. Click Save