If a news item is identical to a news item that appeared in a previous issue of student news, de-emphasize it. How exactly it would be de-emphasized is up for debate.
This would require adding a database. @DanielHarold, what should be the database of choice should someone take on this task?
Instead of de-emphasizing, maybe label with a tag "repeated". I think repeated news items are not necessarily of less interest to readers, so better not to make that assumption.
If a news item is identical to a news item that appeared in a previous issue of student news, de-emphasize it. How exactly it would be de-emphasized is up for debate.
This would require adding a database. @DanielHarold, what should be the database of choice should someone take on this task?