public IActionResult Create([Bind("StudentId,CourseId,Value")] GradeViewModel gradeViewModel)
        {
            try
            {
                if (ModelState.IsValid)
                {
                    _classroomService.InsertGrade(gradeViewModel);
                    return(RedirectToAction(nameof(List), new { id = gradeViewModel.StudentId }));
                }
                return(RedirectToAction(nameof(List), new { id = gradeViewModel.StudentId }));
            }
            catch (Exception ex)
            {
                gradeViewModel.Student = _classroomService.GetStudentById(gradeViewModel.StudentId);
                gradeViewModel.Courses = _classroomService.ListFreeCoursesByStudent(gradeViewModel.StudentId);

                return(View(gradeViewModel));

                throw;
            }
        }