public ActionResult MarkHandler(FormCollection form)
        {
            string username    = form["username"].Trim();
            string classId     = form["classId"].Trim();
            int    classNumber = Convert.ToInt32(form["classNumber"]);
            int    score       = Convert.ToInt32(form["score"]);

            Homework homework = new Homework()
            {
                StudentUsername = username,
                ClassId         = classId,
                ClassNumber     = classNumber,
                Score           = score
            };

            HomeworkModel homeworkModel = new HomeworkModel();

            homeworkModel.Update(homework);
            return(RedirectToAction("ViewHomework", new  { classId, classNumber }));
        }