Is discussing a person's grades, when they are not pleased with that, considered a violation of their honor?

Speaking about a person in a way they dislike constitutes forbidden backbiting, as the Prophet (peace be upon him) said: "Your mention of your brother with what he dislikes." If what you say is true about him, then you have backbitten him; and if it is not true, then you have slandered him. So, if you speak about a person in their absence, saying that they failed in their studies or that their grades are poor, with the intention of belittling them, then you have backbitten them.