Creating Subjects or course

Dear sir,
please i will be glad if you can put me through on this issue.\
i want to add subjects in schooltool, but my dilemma is that i don't know if i
should create subjects for every room or i only need to create for every grade level.
below is a brief description of Nigeria education system in the secondary school:
the secondary school is divided into two parts, junior high school and senior high school.
the junior and senior are divided into 3 grade levels each.
in a typical school there might be as many as 3 to 5 rooms of about 25 students ,
in my own school we have it as follows:

JSS1A,JSS1B & JSS1C (JSS=junior secondary school)
JSS2A,JSS2B & JSS2C
JSS3A,JSS3B & JSS3C
Using Math as an example, do i have to create Math 01A,Math 01B etc or just "Math" is ok\

THANKS.