The Authors Widget plugin is an excellent way to quickly access all of a given student's posts in WordPress.

Activating and applying the Authors Widget plugin

Log into the WordPress Dashboard
Navigate to the Widgets page. To find the Widgets area, hover or click on the Appearance link to reveal a sub menu which includes Widgets.
Find and drag the Authors Widget into the Sidebar area of your choice.
Expand the Authors Widget to edit the settings.

Some recommended settings

Give the Authors Widget a title.
Set the Format to list.
Set to Order by display name
Check the box next to Show post counts. This is helpful in quickly taking count of how many posts students have made.

Note: At first you will only see names of users who have already created posts. Once a student creates their first post they will be added to the list.

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