If class materials uploaded by teachers are not visible to their students, it is highly probable that the cause is either a slow internet connection or the teacher's attempt to share a large file, which may result in a delay in loading.

Here's what to do if the file won't load at all.

If a student cannot view what the teacher is seeing, the quickest solution is for both parties to refresh their whiteboards. This can be achieved by selecting the small refresh button at the whiteboard's top left corner.

When you refresh your whiteboard this way, all your annotations will be saved.

If this doesn't work, you may need to close the tab and try to reload the documents again. In this case, though, your annotations will not be saved. It might be worth asking your student to redo their equipment checks before trying this.