public bool DeleteExpectation(LessonExpectation expectation)
        {
            try
            {
                CurLesson.LessonExpectations.Remove(expectation);

                try
                {
                    Helper.Session.DbContext.Delete(expectation);
                }
                catch
                {
                    // This error is generally caused by a user deleting an item
                    // before it has been saved to the database.
                    // Because of this, we can ignore this error
                }

                return true;
            }
            catch
            {
                //An error occured while deleted the document record
                return false;
            }
        }
        /// <summary>
        /// Create a lesson expectation for the given lesson and expectation if one doesn't already exist in the current lesson
        /// </summary>
        /// <param name="exp"></param>
        /// <returns></returns>
        public LessonExpectation AddLessonExpectation(Expectation exp)
        {
            LessonExpectation lsnExpectation = new LessonExpectation();

            try
            {
                //Make sure the expectation hasn't already been added to the lesson
                if (CurLesson.LessonExpectations != null)
                {
                    foreach (LessonExpectation lsnExp in CurLesson.LessonExpectations)
                    {
                        if (lsnExp.SENumber == exp.Senumber)
                            return null;
                    }
                }

                lsnExpectation.Expectation = exp;
                lsnExpectation.Lesson = CurLesson;
                lsnExpectation.LessonDOK = 0;
                lsnExpectation.LessonID = CurLesson.ID;
                lsnExpectation.SENumber = exp.Senumber;
                lsnExpectation.UnitDOK = 0;

                return lsnExpectation;
            }
            catch
            {
                //An error occured
                return null;
            }
            finally
            {
                lsnExpectation = null;
            }
        }