Shut down the Mac and press Commnd+R together before turning the system on, and then press and release the power button.

Make it easy and force a reset in Jamf before handing it back.

NOTE: You may have to reset the user’s password as well.

Reset the password and the machine should be good to go.

Click on Utilities at the top bar and find Terminal.

Any good MDM allows you to force sign out and remove activation lock if needed. If you know none select forgot all passwords.

The Mac will ask for a known user account that's an admin.

Let the Mac boot - no intervention is needed.

Press and hold the power button until you see the startup options.

If it isn’t managed or all else fails, use Terminal: A lot of MDM solutions “escrow” the FileVault key, so you need to call for this 99% of the time. I mention this because you said you work for a school district. If nothing works, the password needs to be reset by IT - especially with MDM.

If you see “profiles” in System Preferences, then it’s managed.

On a normal Mac me or you would buy retail (which will not be managed, it’s added after the fact) the account will not lock this way - M1 might stop you for 5 minutes and go up until you have to on an M1 but Intel Macs permit unlimited chances. Is it have MDM like Jamf or Apple Business Manager? If it does, that’s a setting that can be enabled.

How to change admin on macbook air