Adding blocks to activities
Certain activity modules, such as the Lesson module and the Quiz module, support blocks on their pages. The site administrator must turn this function on so that the teachers will be able to add side blocks on those pages, otherwise the interface does not show this feature to the teacher.
By default, this feature is disabled in the Site administration block. An administrator can enable it by checking the showblocksonmodpages box in Administration > Appearance > Themes > Theme settings. When enabled, users who can manage course activities will be able to add blocks to pages.