lesson

Count what is really inside

1 · Learn

Trace instructions in their actual order. In 'repeat 3: move 2, turn right', both actions happen three times. A command after the loop happens only after the loop finishes.

A bug may be a wrong repeat count, wrong unit, missing event or command outside the intended block. Change the identified cause and rerun from the same start.

Check startTrace each repetitionCheck commands outsideRetest
Key words and supplied examples.

2 · Worked example

A shape should move four times but moves five. I inspect the repeat count and any extra move after the loop, rather than changing random numbers.

3 · Your turn

Repeat 3 times: add one dot. After the loop, add one more dot. How many dots are added?

Check your answer

Four: three from the loop and one after it.

4 · Apply your learning

Create a short program with one deliberate loop mistake. Ask a partner to predict and explain the first mismatch, then fix and retest it.

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Use an adult-approved offline or school-managed application and invented non-personal data. Do not change real network settings, publish recordings or upload others' images. Follow paper models with practical work in a suitable tool and check saved files reopen.

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