User (id_user, username, password, email, created_at) Administration (department) Teacher (id_teacher, hire_date, department) Rating (id_rating, rating, explanation, id_teacher) Subject (id_subject, name, description) Course (id_Course, num_of_classes, created_by) Class (id_class, start_time, end_time, duration, teacher_id) Student (id_student, progress_score) Enrollment (id_enrollment, id_student, id_Course, status, en_date) Assignment (id_assignment, description, score, deadline) Submission (id_submission, id_student, id_assignment, submitted_at, progress_score) Attendance (id_attendance, id_student, id_class, attended) Subject_Course (id_subject, id_Course) Course_Assignment (id_Course, id_assignment) Course_Class (id_Course, id_class)