public IHttpActionResult AssignStudentToClass(string studentId, int classId)
 {
     try
     {
         var retVal = service.AddStudentToClass(studentId, classId);
         logger.Info("Added student {0} to class {1}", studentId, classId);
         return(Ok(retVal));
     }
     catch (Exception e)
     {
         logger.Warn("Exception caught with message {0}. Returning bad request.", e.Message);
         return(BadRequest(e.Message));
     }
 }