The STEMscopes system will maintain records for campuses that you have been associated with in the past. If you are able to login but as a teacher not not see your classes, or as a student can not see your assignments, make sure you are connected to the correct campus.
In the top right click on your username. At the bottom of the drop-down will be a list of your Schools. Simply select the campus you are currently enrolled in. The system should remember the last campus you were active in.