lesson
A variable stores a value that can change
1 · Learn
A variable gives a stored value a name. In a game, score might begin at 0 and change when a correct action occurs. Setting score to 1 replaces the value; changing score by 1 adds to its current value.
Choose names that explain the value's job. A display of the score is not the same as the stored variable, and a variable in memory is not automatically saved after the program closes.
2 · Worked example
Starting at score 0, changing by 1 twice gives 2. Setting score to 1 twice leaves 1. The commands are not interchangeable.
3 · Your turn
Score starts at 4. It changes by 3, then is set to 2. What is its final value?
Check your answer
2. The final set command replaces the earlier value of 7.
4 · Apply your learning
Trace and run a short approved block program using both set and change commands; compare your predictions.
Adult guidance and safety
Use a school-approved offline or supervised tool and fictional data. Keep work private, respect media permissions and check accessibility. Paper traces support understanding but do not replace running, saving and testing a real project. Do not enter passwords, addresses or other personal details into exercises.
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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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