Add materials. When you add materials to the Classwork page, you can: You can add attachments to your material, such as files from your computer, Google Drive files, YouTube videos, or links. Important: Google Drive items are view-only to students and editable by co-teachers. To change these sharing options, go to Stop, limit, or change sharing. More @Wikipedia
Hover over any link to get a description of the article. Please note that search keywords are sometimes hidden within the full article and don't appear in the description or title.