My Girlfriend received a 1098 mortgage interest statement from her teacher.

My girlfriend received a 1098 mortgage interest statement from her teacher to file woth her taxes? Its a small private massage school. She didnt file it, becuase she didnt know how to factor it in? Im confused as this is out of the ordinary for both of us and it sounds like some sort of error id like to understand? Every search brings me to 1098-t which makes sense but isnt what im searching for. Why did she receive this from a teacher like its important?