Grades
'grades' is the definition.
('mark' can be a synonym of 'grade')
This is the entire clue.
(Other definitions for marks that I've seen before include "Goals" , "Former German currency" , "Visible signs" , "Targets" , "See 8" .)
'grades' is the definition.
('class' can be a synonym of 'grade')
This is the entire clue.
(Other definitions for classes that I've seen before include "See 1" , "Categories" , "Groups with the same social or economic status" .)