Review the article's history
Looking at the edit history of a bad article can give important context for how to go about fixing it. From the live article on Wikipedia, click "View history" at the upper right.

The history page shows the timestamp of each edit, the username of the editor, the size of the article and how much it changed by, and the edit summary that (ideally) describes what was changed.
The history lets you view older versions and to see what changed between different versions. Click a timestamp to view the article at that point. Click prev to compare that version to the one immediately previous, which shows exactly what was changed in that single edit. Click cur to see cumulative changes between that version and the current one. You can also select any two versions and then click Compare selected revisions to see what changed between them.

Have all the recent edits come from students, or have other editors been active on the article as well?