I am so confused of the possessive s

[kwfine]

Hi Alan,

The students of each subject have to make sure they have done their homework and bring their homework back to school.
The tutor of each subject will correct the homework for their students.
what is the difference between these three:
(1), My school's homework tutor
vs
(2), my school homework's tutor
vs
(3), my school homework tutor (without the possessive s)

Thank you.

Kitty

[Alan]

(1) and (3) are possible (with a slight difference of meaning that you should be able to work out by yourself).