R’ Moshe Feinstein wrote a teshuva on this (Igros Moshe CM 2, 30), where he said it’s assur. Here is part of the teshuva:
This is forbidden not only by the law, but also by the Torah. And this is not only misleading, which is in itself forbidden as [the Talmudic sage] Shmuel states . . . that it is forbidden to mislead [any other person], so much the more here that he misleads everybody. It is actual stealing, for when he wants later on to get a job, work in a trade to make a living, in most cases [the employer] wants someone who excelled in his studies. And they will see his test results that he has a good score, and on that [false] basis he will be taken on, and this is actual stealing.
And don’t claim that even if that is the basis for his being hired, this is really an irrelevant basis and therefore it’s permissible to lie. First of all, even if there is no real basis for insisting on [good grades], this employer at any rate insists on it and so his hiring is null and void; and in any case it is always forbidden to lie even if there is no [unfair] advantage gained. . . Furthermore, if [the employer] knew he had lied he wouldn’t rely on him for anything, and he will [unfairly] cause others to be suspect. . . Furthermore, when people insist on this there is certainly a valid basis, for there are certainly things that someone expert in his studies will do better in business and commerce. . . This also develops habits of not knowing what is studied and habituates to laziness.