Is the supplication, "O Lord, make me get a perfect grade in this subject," or "O Lord, make me first in my class," considered an transgression in supplication?

Your mentioned supplication is not an transgression in supplication; rather, it is of the kind of supplication for worldly matters, and it may or may not result in good. It is better to supplicate with the reported supplications. There is no harm in the mentioned supplication, and it is good to ask Allah for provision along with seeking reward in studying and earning, just as Mu'adh sought reward in his sleep and his standing.