Good Afternoon @richard_mckenzie!
Thank you for your post. In order for a class to show up in "Testing Center," you will want to make sure there are course sections that have the standards you have selected mapped to the courses.
It is possible to map standards to course sections within "Classroom Manager". The following article from our Knowledge Base may be a helpful resource for mapping course sections:
Teachers are able to use these steps to map their own course sections using the same steps. If you require further assistance, you will want to contact Support via Live Assist or submit a case here: https://help.powerschool.com/t5/Contact-Support-Assessment/ct-p/contact-support-assessment-analytics...
PowerSchool Community Admin