Learning by Doing: CRC Card Basics

If you’ve ever felt stuck when trying to translate a problem into classes and objects, you’re not alone. Many beginners start with overly complex class diagrams or jump straight into code without first understanding the roles and interactions. This section is your chance to reset — not with theory, but through practice.

Here, we focus on how to create CRC cards in a way that builds real understanding. You’ll learn to think in terms of responsibilities and collaborations — the heart of responsibility-driven design. By the end, you won’t just know CRC modeling; you’ll have done it.

This is a beginner-friendly CRC modeling guide grounded in real exercises. You’ll walk through each step, from setting up a CRC session to modeling a simple banking system — all while gaining clarity on how objects work together.

What This Section Covers

Each chapter builds on the last, guiding you from setup to application in a structured, practical way.

• Setting Up a CRC Session: People, Cards, and Objectives – Learn how to organize a productive CRC card workshop, assign roles, and ensure your team stays focused on the goal.
• How to Write a Good Responsibility – Discover how to phrase responsibilities clearly and concisely, avoiding vague language and overlapping duties.
• Modeling Collaborations that Make Sense – Understand how to capture logical interactions between classes, ensuring your early model stays cohesive and realistic.
• Hands-On Exercise: Modeling a Simple Banking System – Apply what you’ve learned with a guided CRC modeling exercise in a familiar domain — perfect for object modeling practice.
• Visualizing CRC Cards in Visual Paradigm – See how to bring your cards to life digitally, linking them to class diagrams and other artifacts in your design workflow.

By the End, You Should Be Able to…

• Set up and facilitate a CRC card workshop with confidence
• Write clear, actionable responsibilities using object design principles
• Identify and model meaningful collaborations between classes
• Complete a CRC modeling exercise in a real-world domain like banking
• Use tools like Visual Paradigm to visualize and refine your CRC cards
• Apply CRC modeling guide concepts to future software design tasks

There’s no perfect way to start — but a well-structured CRC card tutorial is a great one. This section equips you with the tools and mindset to move from abstract thinking to tangible design, one card at a time.