Please be advised, in order to stop PS from automatically populating student's work into Google drive, it's best to not use handouts/handins from Google Drive. I have attached a Knowledge Base article that will walk you through the steps to manage Google Drive.
I'm confused about those directions - even if you follow them doesn't the document still go into our drive as well? It makes our shared with us section of the google drive almost inoperable and unsearchable.
Thank you for your feedback! Students should be able to select 'attach as files' instead of uploading the file into Google Drive when submitting work through PowerSchool Learning.