Do you have high notes on a subject or for a subject (as in school)?
NoSo never notes in the context of school (i.e. the mark you get for a test)?
NoOr is this just informal language?[STRIKE]?[/STRIKE]
YesAnd high marks/grades in/for is correct?
This usage of notes is BrE. In AmE we get marks, never notes.
Note is used in German.It's not BrE- it sounds like a translation of the term used in some Latin languages.