This video shows you how to recognise when something is hidden (in accessible) to students and how to make it available.
Relevant to Moodle 3.6 from July 2019 onward
It is possible to hide individual resources, sections, topics and even entire modules. The easiest way to tell if something is hidden is the colour. Hidden items are usual shown as 'greyed out.'
In many cases, there will also be a purple message.
When modules are created, they are automatically hidden and will appear as 'greyed out.' This ensures that editing teachers can organise and finalise the layout of a module before making it available to students.
When the module is ready to be shown, follow these steps:
(Clicking Hide again will make the entire module invisible to all students.)
It can be useful to hide sections or topics from student view if there are materials you'd prefer to be unavailable.