Lesson Plan

• Describe the purpose of each validation technique (presence, range, type, length, format, check digit).
• Explain how to implement these checks using simple pseudo‑code.
• Apply appropriate validation rules to a sample data‑entry form.
• Evaluate the effectiveness of a validation sequence in preventing common input errors.

• Projector and screen
• Computer with an IDE (e.g., VS Code)
• Sample web‑form worksheets
• Printed handout of the validation techniques table
• Luhn‑algorithm calculator (online or spreadsheet)
• Whiteboard and markers

Start with a quick scenario: a user mistypes a credit‑card number and the system accepts it, leading to a costly error. Review students’ prior knowledge of basic input checks and set the success criteria: they will be able to design and code a full validation sequence for a form.

1. Do‑Now (5') – short quiz on common data‑entry mistakes.
2. Mini‑lecture (10') – overview of the six validation techniques with real‑world examples.
3. Guided coding demo (15') – implement presence, type, and length checks in the IDE.
4. Pair activity (15') – add range, format, and check‑digit validation to a sample registration form.
5. Form testing (10') – groups exchange forms, test for errors, and provide feedback.
6. Plenary (5') – recap key points, answer questions, and preview next lesson.

Summarise how each technique contributes to data integrity and ask students to write one exit‑ticket sentence describing the most important validation step for a credit‑card field. Assign homework: create a simple HTML form that incorporates all six validation checks.