Re: getting high grades.
Could you ask your question more simply? I don't understand that basic point.
If someone say "May daughter is getting high grades" I would infer that she has mostly As in her various subjects on her report card. However, it could also be that she's getting scores of, say 97 or above, on her tests and papers, and the quarterly grade hasn't come out yet.
In my childrens' schools, they don't get an "A" or a "B" on an individual test or paper. They get a numeric grade. At the end of the marking period, those scores are weighted and averaged and a final number grade is calculated and the A, B, etc. is based on that number.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.