Access Boss

Access Boss gives you the ability to restrict access to your computer to only certain users.

So you can limit the number of accesses per day, per week, or how many times per day. You can also set a maximum time for working on your computer for each user. If a user tries to log in during the limited time, he/she will be alerted by a warning dialog. If the maximum time is exceeded, the user can be logged out or the computer can be shut down, for both of which the time until which the computer will be shut down can be set.
Another feature of the app is statistics, so you have an overview of who is logging in and when.