grading vs scoring

grading and scoring both are nouns.

Word	Noun	Adjective	Verb	Adverb
grading	Yes	No	No	No
scoring	Yes	No	No	No

As nouns, grading and scoring are synonyms defined as:

grading and scoring: evaluation of performance by assigning a grade or score

Other synonyms of grading include marking.

grading (noun)	scoring (noun)
the act of arranging in a graduated series	evaluation of performance by assigning a grade or score
evaluation of performance by assigning a grade or score
changing the ground level to a smooth horizontal or gently sloping surface