Python basics - Day 28

Day 28 – OOP Mini Project: Student Management System

Project: Build a complete Student Management System that demonstrates class design, encapsulation, and data management using OOP principles.

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01. Project Goal

By the end of this project, you will be able to:

• Design and implement multiple interacting classes
• Manage a list of objects efficiently
• Apply encapsulation using private attributes and properties
• Perform CRUD operations (Create, Read, Update, Delete) on objects

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02. System Design

We will build two main classes:

1️⃣ Student

Represents individual students.

• Attributes: name, student_id, grade
• Methods:
  • introduce() → print student details
  • grade (property) → getter and setter with validation

2️⃣ StudentManager

Handles the list of all students.

• Attributes:

  • students → a list storing Student objects

• Methods:

  • add_student() → add new student
  • remove_student() → remove by student ID
  • print_all() → display all students

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03. Implementation

class Student:
    def __init__(self, name, student_id, grade):
        self.name = name
        self.student_id = student_id
        self.__grade = grade   # Private attribute

    @property
    def grade(self):   # Getter
        return self.__grade

    @grade.setter
    def grade(self, value):   # Setter with validation
        if value in ["A", "B", "C", "D", "F"]:
            self.__grade = value
        else:
            print("Invalid grade")

    def introduce(self):
        print(f"Name: {self.name}, ID: {self.student_id}, Grade: {self.__grade}")


class StudentManager:
    def __init__(self):
        self.students = []   # Store multiple students

    def add_student(self, student):
        self.students.append(student)
        print(f"Student {student.name} added.")

    def remove_student(self, student_id):
        self.students = [s for s in self.students if s.student_id != student_id]
        print(f"Student with ID {student_id} removed.")

    def print_all(self):
        print("=== Student List ===")
        for s in self.students:
            s.introduce()

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04. Example Usage

# Create the manager
manager = StudentManager()

# Add students
s1 = Student("Sabin", "S001", "A")
s2 = Student("Anna", "S002", "B")
s3 = Student("Tom", "S003", "C")

manager.add_student(s1)
manager.add_student(s2)
manager.add_student(s3)

# Print all students
manager.print_all()

# Update grade
s2.grade = "A"
manager.print_all()

# Remove a student
manager.remove_student("S003")
manager.print_all()

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05. Expected Output

Student Sabin added.
Student Anna added.
Student Tom added.
=== Student List ===
Name: Sabin, ID: S001, Grade: A
Name: Anna, ID: S002, Grade: B
Name: Tom, ID: S003, Grade: C
=== Student List ===
Name: Sabin, ID: S001, Grade: A
Name: Anna, ID: S002, Grade: A
Name: Tom, ID: S003, Grade: C
Student with ID S003 removed.
=== Student List ===
Name: Sabin, ID: S001, Grade: A
Name: Anna, ID: S002, Grade: A

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06. Key Concepts Used

Concept	Description
Encapsulation	Protected grade attribute using a private variable and property.
Property Decorators	Used @property and setter for controlled access.
Class Interaction	StudentManager manages multiple Student objects.
List Comprehension	Used to filter students during removal.

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07. Reflection

You have now completed the basics section of your Python journey 🎉
You learned how to:

• Model real-world entities using classes and objects
• Apply encapsulation, inheritance, and properties
• Design structured, maintainable OOP systems
• Combine all these ideas into a working mini project

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Congratulations! You’ve completed the Python Fundamentals (Days 1–28) 🎯