[@Aristocles]
To signify rank and or year level I think a bandana would be pretty cool, coloured bandanas which you tie to your arm, leg, head, neck... etc. each colour representing grade.  There might be three year levels; the juniors, midyears and seniors, each having more qualifications, pathways and options.


[hider=Junior school]
I symbol

Blue: A junior student who has just joined the school, they are fresh faced and are not permitted to have a vocation.  Blue grade juniors will take entry level classes based on fitness, tertiary subjects and basic combat.

Green: A junior student who has ranked up from the blue grade, they are permitted to have a primary vocation but will still have to take other vocational classes.  Green grade juniors will take advanced entry level classes based on fitness, endurance, gymnastics, tertiary subjects and vocation based combat.

Red: A junior student who has passed the blue and green grade, they are permitted to choose a primary vocation and a secondary vocation if they so desired.  The red grade juniors will take basic classes based on their vocation, for example: a warrior would take advanced physical training and learn weapons combat, to begin with they will learn swords and shields but in the midyears and senior years they will learn everything from battle axes to flails.
[/hider]


[hider=Midyears]
II symbol

Every midyear student is in the same class as their vocation, they learn basically the same things but each grade has a different level of mastery than their predecessors, however, in tertiary classes not related to vocation they are separated.

Blue: A midyear student will take vocational classes like red grade juniors, they are in seperate classes based on vocation but in the same class as every other grade in the year level.  The blue grade student takes basic vocational classes and tertiary subjects, warrior example: the blue grade student will learn in the same class as his peers and is taught one on one by them in certain situations.  They will take practical lessons with them and join them on outings, however, when the blue grade is taking a tertiary subject they will split from the tri grade class and learn within his own grade.

Green: A green grade student takes classes much like the blue grade, they are, however, permitted to take lessons in other weaponry or spells from their peers.  A warrior example: the green grade student will learn in the same class with blue and red, they will even teach the lower grade what they have learned.  The green grade warrior is permitted to learn basic skills in weapons other than the sword such as maces and great swords, they cannot master the weapon until red grade and the senior school.  As like the blue grade, when the green grade has a tertiary lesson then they will split from the tri grade class and learn with his own grade.

Red: The red grade student will take lessons like the predecessing grades, this grade, however, has more of an insight into the senior year, they will take mastery level classes with the blue and green grades, they will learn advanced combat and weapons and magic training, the grade is encouraged to teach their predecessors based on their knowledge of the class.
[/hider]


[hider=Senior school]
White III symbol

Black grade: the senior school is made to take an apprenticeship with one of the masters or teachers, they learn expert mastery with their preferred weapon, magic and styles, they can take quests with their master and the master can assign quests to them.  They are permitted to teach classes at the school if they are able and they usually take their time to train and study personally, they have less lesson blocks in their time tables and can leave the school at will.
[/hider]

It's what I have so far as suggestions go... 😓