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It is possible to hide a whole section or topic from students
- Navigate to the relevant Moodle module.
Click on the 'Turn Editing on' button in the top-right 
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If a section is hidden, it will say 'Hidden from students
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' under the
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title of the section (see below)
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3. Visibility of items can be toggled by clicking Edit, then selecting 'Hide' or 'Show' from the option list.
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4. When finished click on the 'Turn editing off' button in the top right of your Moodle pagepage 
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NOTE: You may have to refresh or reload your web page (use the option in your browser) to see the grey disappear.
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Visibility is set by opening the Edit menu next to the item and selecting 'Hide' or 'Show' as required. Make sure you have turned the editing on your page beforehand.
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What about assignments?
If an assignment is hidden then students will NEITHER see the assignment NOR their marks.
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