Understanding the Fundamentals of Object-Oriented Programming: A Comprehensive Guide with Python Examples

📘 Lesson Plan: Introduction to Object-Oriented Programming (OOP) in Python

🎯 Learning Objectives

By the end of this lesson, students will be able to:

• Understand the core concepts of OOP: Classes, Objects, Encapsulation, Inheritance, Polymorphism, and Abstraction.

• Write Python classes and instantiate objects.

• Use inheritance and method overriding to create reusable and extensible code.

• Apply encapsulation using private variables and getter/setter methods.

• Recognize and apply abstraction using abstract base classes.

🧠 Key Concepts & Examples

1. Classes and Objects

• Class: A blueprint for creating objects.

• Object: An instance of a class.

Example:

2. Encapsulation

• Protects internal state by making attributes private and providing public methods to access or modify them.

Example:

3. Inheritance

• A class can inherit methods and properties from another class.

Example:

4. Polymorphism

• Different classes can implement the same method differently.

Example (method overriding):

5. Abstraction

• Hides complex implementation and exposes only what’s necessary.

Example:

🏁 Assignment

Create a class Person with the following:

1. Attributes: name and age

2. Method: introduce() that prints:
   "Hi, I'm {name} and I'm {age} years old."

Create a subclass Student that:

1. Inherits from Person

2. Adds an attribute: school

3. Overrides introduce() to print:
   "Hi, I'm {name}, I'm {age} years old and I study at ."

Expected Usage

✅ Answer Key

🔁 Recap

• Class & Object: Template and instance.

• Encapsulation: Protect internal state.

• Inheritance: Reuse code from base classes.

• Polymorphism: Different classes share interface but act differently.

• Abstraction: Hide complexity using interfaces or base classes.