lesson
Make permitted transitions explicit
1 · Learn
A state machine represents named states and allowed transitions. An assignment might move from draft to submitted to reviewed. A transition can require conditions, such as valid content before submission.
Drawing states is not enough: define what happens to data and permissions during each transition. Reopening a reviewed item should follow an explicit rule rather than silently erasing its history.
2 · Worked example
A submit action from an empty draft can be rejected while keeping the draft intact. A successful transition records the submission time and version.
3 · Your turn
Why should changing a reviewed submission back to draft not silently erase the reviewed version?
Check your answer
The previous version is part of the record and may be needed to understand feedback and decisions.
4 · Apply your learning
Draw a state diagram and list one permitted and one forbidden transition with reasons.
Adult guidance and safety
Use an approved sandbox, invented data and test accounts. Do not probe other systems or expose credentials. Retain test evidence and accessibility checks; these teaching models are not a completed practical project or a specified GCSE qualification.
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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.
Powers, roots and trigonometry · Year 7 onward
Use only when the task allows a calculator. Choose one operation at a time and record your working. Trigonometry here always uses degrees (DEG), not radians. Inverse sine, cosine and tangent return an angle, not a reciprocal. Keep exact fractions and π in answers when requested.
Approximate numerical results use up to 12 significant digits. Inverse sine returns −90° to 90°, inverse cosine 0° to 180°, and inverse tangent −90° to 90°; these are principal values, not every possible solution of a trigonometric equation.
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Year 11 Computing learning routine
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