-классник означает в английский

grade [grades]▼(student of a particular grade)
noun
[UK: ɡreɪd] [US: ˈɡreɪd]

grader [graders]▼(one who belongs to a certain grade at school)
noun
[UK: ˈɡreɪ.də(r)] [US: ˈɡreɪ.dər]