When learning object-oriented programming (OOP) using C++, students should focus on understanding and applying the core concepts and principles of OOP. Here are some key things that students should learn:

1. Classes and Objects:

Students should understand the concept of classes and objects. A class is a blueprint for creating objects, and an object is an instance of a class. They should learn how to define classes, create objects, and use them to represent real-world entities or concepts.

2. Encapsulation:

Encapsulation is the principle of bundling data and related methods together within a class. Students should learn how to define class members (variables and functions) as private, protected, or public to control access to the data and provide an interface for interacting with the object.

3. Inheritance:

Inheritance allows students to create new classes based on existing classes, inheriting their properties and behaviors. They should learn how to derive classes from base classes and understand concepts like single inheritance, multiple inheritance, and hierarchical inheritance. They should also grasp the idea of derived class specialization and polymorphism.

4. Polymorphism:

Polymorphism enables objects of different classes to be treated as objects of a common base class. Students should learn about function overloading (having multiple functions with the same name but different parameters) and function overriding (providing a different implementation of a base class function in a derived class).

5. Abstraction:

Abstraction focuses on hiding unnecessary details and exposing only essential information to the user. Students should learn how to design abstract classes and interfaces that provide a clear contract for derived classes to follow.

6. Composition and Aggregation:

Students should understand the concepts of composition and aggregation, which represent relationships between classes. Composition implies a strong ownership relationship, where an object contains other objects as part of its structure. Aggregation represents a weaker relationship, where objects are associated but can exist independently.

7. Object-Oriented Design Principles:

Students should learn about design principles such as SOLID (Single Responsibility, Open-Closed, Liskov Substitution, Interface Segregation, and Dependency Inversion) to guide them in creating well-structured, maintainable, and extensible code.

8. Memory Management:

Although C++ provides manual memory management, students should learn about the role of constructors, destructors, copy constructors, assignment operators, and smart pointers to handle memory allocation and deallocation safely.

9. Exception Handling:

Students should understand how to handle exceptions using try-catch blocks to gracefully handle errors and prevent program crashes.

10. Design Patterns:

Introducing students to common design patterns like Singleton, Factory, Observer, and others can help them understand common software development practices and enhance their problem-solving skills.

In addition to these technical concepts, students should also learn to write clean, readable, and maintainable code by following coding conventions, commenting their code, and understanding good software engineering practices.

Remember that practice is key to mastering these concepts. Encourage students to work on programming exercises, projects, and real-world applications to solidify their understanding and gain hands-on experience.