1
general::
Satisfy the requirements, qualify; also, succeed. For example, Angela hoped her work in the new school would make the grade, or Barbara certainly has made the grade as a trial lawyer. This expression uses grade in the sense of "accepted standard." [c. 1900]
American Heritage Idioms
2
general::
Phrase(s): make the grade
to be satisfactory; to be what is expected. • I’m sorry, but your work doesn’t exactly make the grade. • This meal doesn’t just make the grade. It is excellent.
McGrawhill's American Idioms And Phrasal Verbs