[Vanitas]

The teacher just wants you to try your best, like the others have said above, he may care about his students and just singles you out because maybe he believes you can strive to be a better student and be successful in the world. I've had teachers like that in my highschool days and yes it was embarrassing but it taught me to be more responsible and actually study the material so I don't look clueless next class session. I hope it goes well for you and all teachers are different, but don't feel like you are getting beat down by him, just don't give a shit and go on with your business as he will go on his.