lesson
Use expected results to locate the fault
1 · Learn
A test case states the starting conditions, action and expected result. Test normal behaviour, boundaries and invalid inputs. If the result differs, inspect intermediate values rather than changing several parts randomly.
For a rule 'win when score is at least 10', test 9, 10 and 11. A greater-than condition would incorrectly exclude 10. Retest earlier working cases after a fix.
2 · Worked example
At score 10 the game does not win. I discover the condition is score > 10 and change it to score >= 10, then retest 9, 10 and 11.
3 · Your turn
For 'allow when lives > 0', should lives = 0 be allowed?
Check your answer
No. Greater than zero excludes zero; test the exact boundary.
4 · Apply your learning
Write a small test table for your variable-based game, including replay and repeated-contact cases.
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Check a calculation · Year 5 onward
Use this only when your teacher or adult allows a calculator for the task. Show your thinking first. It does not replace mental or written arithmetic and does not mark your lesson answer.
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