Traditionally, Prompt Corner (that small space back stage on the Stage Left side) is where you would call a show from, if you have the facilities.
Calling from the "booth" is a relatively new thing (compared to the age of the stage managers role), which has come about with a lot of theaters either being ex-cinemas, built to be able to act as a cinema or being built with multimedia capabilities (the booth being the projectionists room (bio-box)), and also from 'recent' explosion of black box theatres - at least that is my take on it - SM's moving from black-box and feeling more comfortable in the bio-box, or new SM's feeling more comfortable with the ops in a separate room.
If you plan on being an SM after school, then there is no question where you should call from - Prompt Corner - because chances are, if you ever get into anywhere remotely resembling the "Big time" you will be calling from PC. If you cannot trust your ops, then you may wish to be within hitting distance, so the back of the theatre is a good place, however if you cannot trust your ASM's, then PC once again.