Requirements Modeling with Use Case Diagrams

Objectives

1. Understand the concept of requirements in project development and the importance of modelling them clearly and accurately.
2. Develop skills to create and interpret use case diagrams, a tool widely used in requirement modelling.
3. Apply the acquired knowledge to create practical examples of requirements and use case diagrams, stimulating students' critical thinking and problem-solving abilities.

Introduction (10 - 15 minutes)

1. Review of previous content: The teacher should start the lesson by reviewing the concepts of system development and analysis, focusing on the importance of understanding the users' needs and how this can influence the design of a system. This review can be done through questions to the students or through a brief presentation on key points.

2. Problem situation: Next, the teacher should propose two problem situations that will serve as the basis for the practical activities of the lesson. For example:

   • "Imagine you are developing a new mobile application for managing personal finances. How would you gather and record the users' requirements?"
   • "You have been hired to develop a new e-commerce website. How would you ensure that the website meets all the users' requirements and expectations?"

3. Contextualization: The teacher should then explain the importance of requirements modelling in system development, highlighting how this can save time and money by avoiding the need for future modifications. Furthermore, the teacher can mention how understanding and modelling requirements is a fundamental skill for professionals in the area of technology and information.

4. Introduction to the topic: To spark students' interest, the teacher can share some curiosities or stories related to the topic. For example:

   • "Did you know that poorly defined requirements were one of the main reasons for the failure of many IT projects? This is why requirements modelling is considered one of the most important steps in system development."
   • "Did you know that use case diagrams were created by Ivar Jacobson, one of the founders of the Unified Modeling Language (UML)? They are widely used in the software development industry to represent the users' interactions with the system."

Development (20 - 25 minutes)

1. Presentation of the theory: The teacher should start the theoretical part by explaining the concept of requirements in project development. It is important to highlight that requirements are the characteristics and functionalities that the system must have to meet the users' needs.

2. Types of requirements: The teacher should then present the different types of requirements, such as functional requirements, non-functional requirements, interface requirements, etc. For each type, the teacher should provide examples and explain how they can be modelled.

3. Requirement modelling techniques: Next, the teacher should present some requirement modelling techniques, such as user stories, use case diagrams, sequence diagrams, etc. The focus of the lesson will be on use case diagrams, so the teacher should explain that they are a way of representing the users' interactions with the system.

4. Components of the use case diagram: The teacher should then present the components of the use case diagram, such as the use case, the actor, the system, etc. For each component, the teacher should explain its function and provide examples.

5. Practical activity: Now that the students have understood the theory, it is time for the practical activity. The teacher should divide the class into groups and give each group a problem situation. The students should then discuss and model the requirements of the system described in the problem situation, using the use case diagram.

   • Step 1: Each group should identify the main actors in the system and list the main requirements.
   • Step 2: Next, the students should draw the use case diagram, placing the actors and the use cases.
   • Step 3: Finally, the students should present their diagrams to the class, explaining their choices and answering any questions that may arise.

6. Feedback and discussion: After all the presentations, the teacher should provide feedback to the students, highlighting the strengths and areas for improvement in each diagram. The teacher should also encourage discussion among the students, allowing them to ask questions and share their own insights.

Return (10 - 15 minutes)

1. Group discussion: The teacher should gather all the students and promote a group discussion about the solutions found by each group. This discussion will allow the students to see different approaches to solving the same problem and learn from the others.

2. Connection with the theory: The teacher should then make the connection between the practical activity and the theory presented at the beginning of the lesson. The teacher should highlight how the use case diagrams, as a requirement modelling tool, help to visualize and understand the users' interactions with the system.

3. Individual reflection: Next, the teacher should ask the students to individually reflect on what they have learned. The teacher can do this through questions like:

   • "What was the most important concept you learned today?"
   • "What questions have not been answered yet?"

4. Sharing reflections: After a minute of reflection, the teacher should ask some students to share their answers with the class. This will allow the teacher to assess the students' understanding and identify any areas that may need reinforcement in future lessons.

5. Teacher's feedback: Finally, the teacher should provide feedback to the students on their performance during the lesson. The teacher should praise the students' efforts, highlight the improvements observed, and provide suggestions for future studies. The teacher should also answer any questions that the students may have.

6. Preparation for the next lesson: To end the lesson, the teacher should give a brief introduction to the topic of the next lesson and prepare the students for what they will learn. The teacher can do this by presenting a problem situation related to the topic and asking the students to think about possible solutions.

Conclusion (5 - 10 minutes)

1. Summary and Recap: The teacher should start the conclusion by recapping the key points of the lesson. This includes the definition of requirements in project development, the importance of modelling them clearly and accurately, and the use of use case diagrams as a tool for this modelling. The teacher can do this through a brief slide presentation or an oral summary.

2. Theory-Practice Connection: The teacher should then highlight how the lesson connected theory to practice. This can be done by recalling the problem situations presented at the beginning of the lesson and showing how the students, through the practical activity, were able to model the requirements and create use case diagrams to represent the users' interactions with the system.

3. Extra Materials: The teacher should suggest extra materials for the students to explore in order to deepen their understanding of the topic. This can include books, articles, online videos, and websites related to requirements modelling and use case diagrams. The teacher can provide a list of these resources at the end of the lesson plan.

4. Relevance of the Topic: The teacher should explain the relevance of the topic to the students' everyday lives. This can be done by highlighting how the ability to understand and model requirements is a fundamental skill not only for IT professionals, but for anyone who wishes to work in any area that involves the development of products or services. The teacher can also mention how the use of use case diagrams can help to improve communication and collaboration between the different teams involved in a project.

5. Preparation for the Next Lesson: Finally, the teacher should prepare the students for the next lesson. This can be done by introducing the topic of the next lesson and explaining what the students can expect to learn. The teacher can also present a challenge or a question related to the next topic and ask the students to think about possible solutions. This will help to spark the students' interest and prepare them for the new content.