Apart from enabling Family accounts, Windows lets you add non-family members' accounts like friends. It can be done using their phone number or a Microsoft account. While everything works the same way, the only difference is that they won't get added to your family account, but they still can access your PC. In the same setting, another feature allows you to set up an account to take tests from the same PC using a URL that belongs to School. I am guessing this will only work with schools that have Windows PC.