Can I limit personal Google Drive use for just some staff?

If your licensing includes Microsoft Defender for Cloud Apps, check its app controls and session policies. Depending on your setup, you may be able to restrict Google Drive or other Workspace services for selected users while leaving unrelated Google services available. Confirm the exact capabilities and licensing in your tenant before designing around it.

Test with a small group first, and include desktop sync clients and unmanaged devices in the scope. Browser or network blocks can be bypassed, so treat technical controls as one layer, not a guarantee that files cannot leave.

Make sure there is a clear, approved policy first: company teaching materials belong in organization-managed storage, and personal accounts are not an approved place for them. Supervisors need to communicate and enforce it consistently. If management will not back the rule, a technical block is likely to create workarounds rather than solve the ownership problem.

Also provide a supported place to create and share the materials, with access that remains under the organization when someone changes roles or leaves.

Before blocking anything, ask why staff are choosing Slides. It may be a workflow, collaboration, training, or familiarity issue. If the Microsoft 365 option is awkward for their actual teaching needs, demonstrate a workable alternative and offer help moving existing content.

That will not replace policy or access controls, but it can reduce the incentive to keep using personal accounts.

For company-managed endpoints, browser or network controls can help restrict access for a defined group. Microsoft security tools may offer more targeted controls than blocking all of Google, but coverage varies by license and configuration. Test whether the controls cover the web app, uploads, and sync software, and document what they do not cover.

Personal devices are a different boundary. You generally cannot reliably control activity on devices the organization does not manage, so set expectations for how company data may be accessed and provide an approved route.