KS3 Python 5 Decisions, Decisions

This lesson, titled “Decisions, Decisions,” is the fifth installment in the Year 9 Python series. It introduces the concept of Selection, allowing programs to make choices and follow different paths based on specific conditions.
Core Learning Objectives
• The if Statement: Students learn how to use the if keyword to execute a block of code only when a specific condition is met.
• Comparison Operators: The lesson introduces the syntax for comparing values, specifically focusing on the double equals sign (==) for checking equality versus the single equals sign (=) used for assignment.
• Indentation and Colons: A critical focus is on Python’s structural requirements, such as ending an if statement with a colon (:) and indenting the subsequent lines of code.
• Logical Flow: Students explore how a program skips sections of code if a condition is False, introducing the basics of nested logic where decisions are made within other decisions.
Lesson Structure
• Unplugged Starter: A “Bouncer at the Club” analogy where students act as logic processors, deciding who gets into different rooms based on rules about clothing colors and secret passwords.
• Syntax Breakdown: Direct instruction on the specific “grammar” of an if statement and the common errors (Syntax Saboteurs) that can cause a program to fail.
• Practical Programming Tasks:

1. The Password Protector: Students write a script that asks for a secret word and only grants “access” if the input matches exactly.
2. The Mission File: An exercise in building a multi-stage logic gate where a “Mission Success” message is only displayed if the correct name and security code are entered.
   • Debugging Challenge: Students are tasked with spotting missing colons and indentation errors in broken snippets of code.