...I am compelled to work
harder and try to get higher scores ...
However, certain demerits....
Though the grading system has some negative effects, the merits of it
outweigh its demerits...
Zeal to work more creeps in. Sincerity towards work increases and self confidence boosts up.
Somehow these two sentences sound a little awkward to me... Maybe they were not written clearly enough to support your view?? I really don't know...@@...
To me, the conclusion seems a little bit rush. It is not "the grading system" has
more advantages that encourages students to
learn more. Maybe you could list the specific merits you've explained above in brief before you draw the conclusion.
Wish my views could help. ^_^