lesson
Judge the result against requirements
1 · Learn
A digital project needs explicit requirements, a design, implementation, tests and evaluation. Evaluation compares evidence with the requirements, including failures and limits. It is not simply saying the result looks good.
If a quiz must retain scores after reopening, seeing a score once is insufficient proof. Close and reopen in a controlled test and verify the stored result belongs to the correct test account.
2 · Worked example
Requirement: reject scores outside 0–100. Evidence: tests at -1,0,100,101. A screenshot of the form alone does not prove the rule works.
3 · Your turn
What test would support a requirement that a saved note survives reopening?
Check your answer
Save a known test note, close and reopen the application, then verify the same note is retrieved for the correct test account.
4 · Apply your learning
Create an evidence table linking each requirement to a test result and a specific unresolved issue if it fails.
Adult guidance and safety
Use an approved sandbox with invented data. Never ask for real passwords, personal records or access to another person's system. These text examples need executable projects and assessed evidence in two languages; reading code alone is not practical mastery.
Open your writing and drawing pad
Write, draw or show your working. Use a mouse, pen or finger. This pad is not a submitted answer.
Not saved to your account. Download your drawing as PNG and your typed notes as TXT before leaving or refreshing. They are separate files. Do not enter private information.
Open a picture saved on this device to draw on it again. Opening replaces the drawing, but Undo can restore it. PNG only, up to 4 MB and 4096 × 4096 pixels. The picture stays in this browser; it is not uploaded. Paper lines in a saved picture become part of that picture.
Clear the drawing? Your typed notes will stay. You can undo this action.
Your pad is empty.
Open a UTF-8 TXT file from this device, up to 40 KB and 10,000 characters. It stays in this browser. Opening can be undone until you type again. Downloads keep a new copy; they do not change the file you opened.
Replace the notes on this page with the opened file? Download the current notes first if you want to keep them.
Typed notes are not submitted answers.
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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