Attendance System ER diagram models a comprehensive student attendance tracking platform with nine core entities: students, teachers, courses, class offerings, and attendance records. Data flows from academic_terms and class_offerings through to attendance logs, capturing student check-ins via time_in/time_out and status enums, with unique constraints on student_id, offering_id, and date to prevent duplicate records. This schema enforces referential integrity across enrollment, class scheduling, and attendance capture—critical for educational institutions managing compliance and student accountability. Fork this diagram on Diagrams.so to customize entity relationships, add audit trails, or extend with grade-linked attendance policies. The design uses optional foreign keys (dashed lines) for flexible scheduling and supports multi-term, multi-section class structures typical of K-12 and higher education systems.