Learn from a worked example, then try a similar question

Strong practice materials often show a model so learners can self-teach the next small step. The design risk is familiar: if the worked line is the same item you must submit, you copy instead of encode. RubricMark’s answer is an isomorphic twin — same skill and method family, different surface values.

The four-beat design

1. Author / bank a sample — a real sit stem from the skill ladder (for example, arithmetic sequences).
2. Hold the keyed answer server-side — the runner never ships the mark key mid-sit.
3. Offer a similar worked example — invent or show a parallel question with a full solution path.
4. Return the learner to a new attempt — their pack item, their working, their check.

Why “read then copy the same numbers” fails

Reading a fluent solution to the exact exam item creates an illusion of competence. You recognise the algebra; you have not retrieved it. Isomorphic practice keeps desirable difficulty: you must map the method onto new numbers.

What students should do in a session

• Open the sit item and try 60–90 seconds cold.
• If stuck on method (not arithmetic), open Example and study the twin.
• Close the example. Rewrite the method on your stem without looking.
• Check answer. If wrong, fix the step — do not regenerate a twin that matches your key.

Where Rubi fits (and does not)

Rubi mid-sit help is Socratic: hints only, never the final value. The Example tool is separate — a Pro-modelled worked twin for method study. Use Rubi when you need a nudge; use Example when you need to see a full parallel solution.

Bottom line

Design from a sample, teach on a twin, assess on a fresh attempt. That is the pedagogical contract behind Daily Practice Packs and the Example drawer.