If I make a mistake in the gradebook (say, enter a set of grades incorrectly, or delete grades from the wrong place) and I want to undo the work I've done, how do I do that without just closing the gradebook? If I try to switch windows, my only option is an error message that requires that I save and continue.
When entering grades, if you make several errors and haven't yet saved the changes, you can use your browser's "Refresh" button as a sort of undo button. You may get a prompt warning you that your changes haven't been saved, in which case you can press the Ok or Reload button (depending on your browser). When the page refreshes, it should reload with the data that was last saved in your grade book.