How do I delete a top-level Lessons page?
Deleting a lessons page is a two-part process. First, you must remove the Lessons page from the Tool Menu or page link, and then you can delete it from the site.
From the More Tools drop-down menu, select Remove Page.
You will see the list of pages with the unused pages listed at the bottom. Only items which are not linked from any other location can be permanently removed from the site.
Click Delete selected pages to completely delete the selected page/s from the site.