Teachers spawn at the top of the road like visitors or parole officers and will proceed directly to their classroom. After the class is finished the Teachers will leave at the bottom of the road. It is however recommended to put a guard in the classroom because fights can start in classrooms, although armed guards are not recommended due to the fact that prisoners tend to do worse when they are suppressed.
After building a functional classroom and initiating either the Foundation Education Program or the General Education Qualification program, a teacher will be present during the program's hours of operation.
An important thing to know is that since the foundation education program requires three hours, you need at least a three hour span in which the class can teach. Those hours much be either free time or work otherwise the program will say "No classroom available".