To have a project site show up as "In progress" for the Course overview block, the project site will need to have an end date that is in the future.
To adjust end dates for a course site begin by opening the course site and then locate the Administration block on the right side, then click on Edit Settings.
Under the Course settings locate the "Course end date" fields, set this to a date and time in the future, then scroll down to the bottom of the page and click on "Save and display".