My scenario is that I have ESL (English as a Second Language) teachers who want to comment on student's essays. The essay is an unformatted text (just blank lines separating paragraphs). The nature of the correction is usually word choice, word order, spelling, commas, wrong tense, ...
I am creating a web app that should aid the teacher in making the corrections. It should make the corrections easy to enter and it should present them in such a way that the student can easily go through them.
Currently the web app only allows the teachers to write a text comment below the essay. They usually quote parts of sentences and either write their comments after the quote, or highlight the changes they made by writing changed parts of the sentence in UPPER CASE. Since the essays are very short (about 150 words), this is not as painful as it may sound. I believe that since reading the corrections while having to cross reference their original writing takes some effort from the students, some of them do not pay enough attention to the corrections.
After looking what the teachers do outside of my web app, I found the "Track changes" and "Add comment" features in Microsoft Word. The first one allows to turn on a tracking mode which visually highlights editing changes (red background with strikethrough effect for deleted and green background for added text) and the second feature allows to select parts of the text and attach a side notes to them.
From my experience, this usually works well enough for the teachers, but it is possible that one can do better. Do you know of some examples how this problem can be solved or can you come up with your own solution? Is it a good idea to try to just copy the two Word features?