Teacher Substitution

Overview

The Teacher Substitution feature manages class coverage when teachers are absent. It supports two integrated mechanisms:

Mechanism	Scope	Model
SubstituteAssignment	Daily class-level — specific subject, time slot, class	Educator\SubstituteManagement\SubstituteAssignment
LeaveSubstitute	Leave-based — covers the full duration of a teacher's leave	LeaveManagement\LeaveSubstitute\LeaveSubstitute

Key Entities

Entity	Description
Original Teacher	The teacher who is absent and needs coverage
Substitute Teacher	The teacher who covers the class
SubstituteAssignment	A specific assignment covering one class session (subject + time + class)
LeaveSubstitute	Links a leave request to a substitute employee for the leave duration
Assignment Status	pending, confirmed, completed, cancelled

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Concept

Two-Tier Substitution Model

The system uses a two-tier approach to handle teacher absence:

1. Leave Level — When a teacher requests leave, a LeaveSubstitute record can be created to assign coverage for the entire leave period. This provides a high-level view of who is covering during the absence.

2. Class Level — For each class session that needs coverage during the absence, a SubstituteAssignment is created. This captures the specific subject, class, time slot, and date. Multiple assignments can be created for a single leave period.

Assignment Lifecycle

1. Pending — Assignment created, substitute notified
2. Confirmed — Substitute accepts the assignment
3. Completed — Assignment has been fulfilled
4. Cancelled — Assignment is no longer needed

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Flowchart

Teacher Substitution Flow

The following flowchart illustrates how a substitution is created when a teacher is absent:

Explanation:

1. When a teacher is absent, the system determines if it's planned leave or an emergency.
2. For planned leave, a leave request is submitted first, then a LeaveSubstitute is created.
3. For emergencies, the admin can create assignments directly without a leave request.
4. For each affected class session, a SubstituteAssignment is created with the specific class, subject, and time slot.
5. The substitute receives a pending assignment and can confirm or decline.
6. Once confirmed and taught, the assignment is marked as completed.

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Data Flow Diagram

Level 0 — Substitution Context

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Activity Diagram — Substitution Lifecycle

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Database

Entity Relationship Diagram

Key Tables

substitute_assignments

Column	Type	Description
original_teacher_id	uuid FK	Absent teacher
substitute_teacher_id	uuid FK	Covering teacher
school_class_id	uuid FK	Class being covered
subject_id	uuid FK	Subject being taught
assignment_date	date	Date of substitution
start_time / end_time	time	Time slot
status	enum	pending, confirmed, completed, cancelled

leave_substitutes

Column	Type	Description
leave_request_id	uuid FK	Associated leave request
substitute_employee_id	uuid FK	Covering employee
start_date / end_date	date	Coverage period
status	string	Approval status

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Key Files

app/Models/Educator/
├── Teacher/Teacher.php                                   # Teacher with substitution relations
└── SubstituteManagement/
    └── SubstituteAssignment/
        ├── SubstituteAssignment.php                      # Class-level substitution model
        └── Concerns/
            ├── HasRelations.php                          # Relationships
            └── HasScopes.php                             # Query scopes

app/Models/LeaveManagement/
└── LeaveSubstitute/
    └── LeaveSubstitute.php                               # Leave-based substitution

app/Enums/Educator/SubstituteManagement/
└── AssignmentStatus.php                                  # Status enum

database/migrations/
├── v1_2_0/003_create_substitute_assignments_table.php    # Substitute assignments table
└── v1_2_0/004_add_leave_request_id_to_substitute_assignments.php