lesson
A search engine uses an index
1 · Learn
A search engine gathers information about many pages and builds an index that helps match queries with results. It does not necessarily examine every page freshly at the moment you search.
An index can be incomplete or out of date. A page may change after it was indexed. Search results are a starting point for checking sources, not a guarantee that every result is accurate or suitable.
2 · Worked example
I distinguish a short result snippet from the full page. The snippet may omit context or reflect an earlier version.
3 · Your turn
Does a search result prove the page's information is current and correct?
Check your answer
No. Check the actual source, date, context and corroborating evidence with adult guidance.
4 · Apply your learning
Model an index using six invented page cards and keywords. Compare what your index finds with the content on the cards.
Adult guidance and safety
Use adult-approved offline or school-managed tools, invented data and original media. Keep projects private unless sharing is explicitly approved. Paper traces support, but do not replace, practical programming and saved digital work. No real passwords or personal records belong in these exercises.
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.
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