If someone or something 'makes the grade', they achieve the expected result. They succeed. It is often used in the negative when things are not good enough.
The marking of exams has been tougher this year and many students just didn't make the grade.
This work is awful. It simply doesn't make the grade.
I have every confidence in you and expect you to make the grade.
Don't confuse it with
If you grade someone down on something, you give someone a low score on their performance, perhaps for a particular error.
I’m afraid I had to grade you down on your essay for poor spelling.
There has been a fall in the proportion of A-levels awarded an A or A* grade for the first time in over two decades.
This summer's results show 26.6% of A-level entries achieved the top two grades - down from 27% last year.
About 335,000 students in England, Wales and Northern Ireland have been receiving their results - with many finding out whether they have made the grade for university.