Activity Tab
To see recent activity from any of your students, you can visit the Activity tab of the course. This will provide a list of recent edits made on Wikipedia by any students in the course. Click the "+/-" link to see a summary of the edit in the form of a 'diff' - the differences between revisions.

Students tab
To see recent contributions from an individual student go to the Students tab and click on the row of the student you are interested in. (You can click anywhere except on one of the underlined links, which takes you to Wikipedia.) Clicking the row shows you recent edits that the student has made, and you can click the '+/-' link to see the details. This will also show you date and time stamps of when each student has completed each training.

Alternatively, for any student, you can click on the underlined link of their username to see their full Contribution history on Wikipedia, where you can browse every edit they have made and see individual diffs if you wish.
Articles tab
The Articles tab of your course includes an "Articles edited" section - this is any article on Wikipedia that your students have touched during the assignment, whether it was assigned to them or not.

The far right column includes links to two "assessment tools" - The "Current Version with Authorship Highlighting" button will show you the current version of the article with a color coded highlight of what exactly the student(s) contributed.
In the example below we can see that the username listed contributed the sections and text highlighted in purple.

The "Show Cumulative Changes" button (denoted by the +/-) will open up a "differences between revisions" view. This is copied from the "diffs" on-wiki. The right hand column shows that students have added and the left hand column shows what students have removed from the article.

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