SS 2 Third Term

Lesson objectives

By the end of the week, learners should be able to:

1. Name the selection statements IF, ELIF and ELSE.
2. Write an if statement deciding between two outcomes.
3. Write an elif statement handling a middle outcome.
4. Combine if, elif and else into one robust branch.
5. Trace a combined selection statement predicting the outcome.

Key vocabulary

• Selection: a branch choosing different paths under conditions.
• IF statement: a condition controlling which branch runs.
• ELIF statement: a second condition checked only after the first fails.
• ELSE statement: the final branch running when no earlier condition matches.
• Branch: one of the paths taken by a selection statement.
• Condition: the boolean expression evaluating the branch.
• Outcome: the result displayed when a condition is true.

Common misconceptions

• "IF runs everything." IF runs only when its condition is true; other branches may still run.
• "ELSE covers everything." ELSE runs only when neither IF nor ELIF matches.
• "Every statement needs both IF and ELSE." A pure IF statement handles two outcomes only.

Teacher activities

1. Starter: display an IF and an ELSE statement and ask which runs when a condition is true.
2. Name IF, ELIF and ELSE one by one and demonstrate each on a live system.
3. Write a simple IF deciding between two outcomes.
4. Add an ELIF handling a middle outcome.
5. Combine IF, ELIF and ELSE into one robust branch.
6. Close with the combined-branch task and exit question.

Student activities

1. Answer the starter and state which statement runs under a true condition.
2. Name IF, ELIF and ELSE in their own words.
3. Write a simple IF deciding between two outcomes.
4. Add an ELIF handling a middle outcome.
5. Combine IF, ELIF and ELSE into one robust branch.
6. Trace the combined branch predicting the outcome for each case.
7. Answer the exit question in one sentence about ELSE coverage.

Practical / learning evidence

A combined IF-ELIF-ELSE program with two cases, plus the confirmed outputs for each. Submit both the program and outputs for marking.

Resources and preparation

Computers with the interpreter, blank program windows and sample tracing cards. Prebuild the interpreter in a read-only folder. Disable Caps Lock before typing. Verify the computer starts reliably.

Assessment for learning

Inspect the combined branch for correct IF, ELIF and ELSE syntax. Check the outputs for sensible outcomes. Ask a learner to describe when ELSE runs. Flag any learner who writes IF without ELSE.

Inclusion and homework

Provide the combined branch template prefilled for the conditions and allow oral tracing. Allow extra time on the tracing task. Extend confident learners with three branches and a second homework nesting two selections. Homework: write a program with two nested if statements and display each branch's path.