Lesson Plan

• Describe the purpose and core components of an E‑R diagram.
• Identify entities, attributes, relationships, and cardinalities from a set of requirements.
• Construct a complete E‑R diagram for a given scenario.
• Translate an E‑R diagram into a relational schema with appropriate primary and foreign keys.
• Evaluate diagrams for common pitfalls such as missing keys or unresolved many‑to‑many relationships.

• Projector or interactive whiteboard
• Slide deck showing E‑R diagram components and examples
• Printed worksheet with practice scenarios (library, university enrolment)
• Whiteboard and markers
• Laptops or tablets with diagramming tool (e.g., draw.io) or plain paper for sketching
• Answer key for practice questions

Begin with a quick poll: “What visual tools have you used to plan a system?” Connect responses to the need for a clear, high‑level data model. Explain that today’s success criteria are to produce a correct E‑R diagram and to convert it into a relational schema.

1. Do‑Now (5'): Students list real‑world objects for a simple library system on sticky notes.
2. Mini‑lecture (10'): Review E‑R diagram components and cardinality notation with slide examples.
3. Guided Practice (15'): Walk through the 6‑step construction process using the university enrolment scenario; students sketch each step on paper.
4. Group Activity (15'): In pairs, students create an E‑R diagram for the library scenario using laptops or chart paper; teacher circulates for feedback.
5. Translation Exercise (10'): Each pair converts their diagram into relational tables, identifying primary and foreign keys.
6. Check for Understanding (5'): Quick whole‑class poll of common pitfalls; students correct any errors in their diagrams.
7. Wrap‑Up & Q&A (5'): Address lingering questions and highlight key take‑aways.

Recap the six‑step process and why accurate cardinalities matter for relational implementation. Students complete an exit ticket by writing one tip to avoid a common pitfall. For homework, they must design an E‑R diagram for a simple online store and submit the corresponding relational schema.