By default, a project unit is not available to others until you explicitly publish it. This ensures that you can make changes, even after publishing, without the published course content being affected.
Publishing the unit takes a snapshot of the underlying project unit and assigns it a new version. Once published, you can make further edits to the unit, they will not be visible until you publish the unit again.
Click on Courses on the left-hand side of your screen and select the course you want to preview.
Go to the Edit tab
Click on the assignment name to open and make required changes to it.
When done, click on the Publish button that will show at the top right of your menu bar or go to Education->Publish Assignment to publish the assignment
A dialog will be shown for you to confirm you wish to publish
Existing files in the code workspace are never updated as this can invalidate work for students who have already started the assignment but new files can be added.
Students who haven't started the assignment will see the updated content but those who have already started an assignment will not.