// GET: api/GradesData
        public IHttpActionResult GetGrades()
        {
            var list         = db.Grades.ToList();
            var wrapperClass = new GradeApi {
                Grades = list
            };

            return(Ok(wrapperClass));
        }
        public async Task <IHttpActionResult> GetGrades(int id)
        {
            var list = new List <Grade>
            {
                await db.Grades.FindAsync(id)
            };

            if (list == null)
            {
                return(NotFound());
            }
            var wrapperClass = new GradeApi {
                Grades = list
            };

            return(Ok(wrapperClass));
        }