This invention concerns a document markup tool, that is an application where existing authored documents can be marked or annotated. For instance, formative or summative assessment submissions authored by students might be graded by a teacher using the markup tool. The tool itself is operable by a user at a computer user interface to: Recognize the members of a set of existing documents. Open one of the existing documents in a set and display its contents to a user together with a toolbar. And, select locations in the document and, using the toolbar, add commentary and scores to the document. Wherein the markup tool is automatically operable to: Total the scores made in a document. Display the scores in a graphical report in the document. Display a moderation panel which enables visual and statistical comparisons of the scores made in a document to the scores added to all the documents of the set. And, reflect changes to the scores made in a document in the displayed moderation panel.