Yes, absolutely. As a teacher or School Admin of the system, you can sign up a parent for the time slot they want.
Go to the class signup page and click the blue Sign Up button next to the conference time.
Select the student/parent name from a drop-down menu.
You can add a private note that is not visible to parents.
Click Save.
To cancel an attendance, go to the time slot and click the pen icon next to the parent name. Select Cancel Attendance.