SO THE YOUNGER STUDENTS COULD USE SOME HELP GETTING AROUND HOGWARTS, SO THE PROFESSORS BEGIN TO PAIR OFF OLDER STUDENTS WITH THE YOUNGER STUDENTS TO BE THEIR 'MENTOR' AND HELP THEM AROUND THE SCHOOL.  

MENTORS MUST BE IN THE 4TH YEAR OR HIGHER, AND THE MENTOREE MUST BE 1ST THROUGH 3RD YEAR.  THE WAY IT GOES IS AS SUCH: 

1ST YEARS => 4TH YEAR MENTOR
2ND YEARS => 5TH YEAR MENTOR
3RD YEARS => 6TH YEAR MENTOR

7TH YEARS CAN PICK SOMEONE TO MENTOR IF THEY WISH, AS ITS MORE OF A GUIDE - AFTER ALL IF A FIRST YEAR IS MENTORED BY SOMEONE, THEY COULD GO THROUGH THEIR THIRD YEAR WITH THE SAME MENTOR.

ITS NOT REQUIRED TO FOLLOW THE GUIDE, AND JUST SUGGESTED.  

7TH YEARS CAN BE MENTORED BY A PROFESSOR FOR THEIR FUTURE JOBS.  THEY CAN ALSO HAVE SOMEONE OUTSIDE OF HOGWARTS TO INTERN AT DURING THE WEEKENDS.