Sorting requires one rule applied all the way through

Put a few length cards in order and check every adjacent pair. A mostly correct arrangement can still violate the chosen shortest-to-longest rule, while grouping cards by another property would answer a different task.

To hand: Cards with different lengths drawn.

State the ordering rule. Compare pairs. Check adjacent cards.

Check the complete ordered result

Arranging shortest to longest differs from grouping by colour.

Check the complete ordered result rather than a few appealing pairs. One misplaced item can violate the sorting rule despite many correct comparisons.

Does every adjacent pair satisfy the rule? Use four cards.

Sorting and categorising are different tasks.

Resources

• Human Robot Commands – Coding Without Screens Printable Game — Check the command conventions before using the sequence or debugging task.

Further reading

• CS Unplugged — Kidbots and algorithm activities
• Australian Curriculum Version 9 — Technologies overview

Read next

• Go over there: let two readers expose the missing instruction
• Test the value on the boundary of the sorting rule
• The same commands can finish differently from different starts

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