hi sunnyman,
my gf was telling me about this post. I'm a black guy in an ivy engineering program. in my phd program i haven't had problems with race so far. i am pretty good with my stuff and did serious research even as an undergrad. i love my stuff so when i work with people they quickly realize they can't put me in any silly box. the former dean of the Yale law school(Asian) once said that his father told him that numbers don't lie so he should study the sciences and math because math has a universal language: numbers. i think there's a lot of room for people to disrespect you in the liberal arts because the arts is so subjective and it's hard to prove people wrong. but you should feel vindicated because it seems u've come far already.
having said that, as an undergrad i took a film class which was divided into groups. i worked with two white students. it hurt me greatly to realize how they ignored me and everything i had to say. people don't respect you if they don't engage you in a serious way. those two kids didn't respect me, never mind that they were always late and never thought about our group work ahead of time. they created a group of two and decided to do the project and give me the introduction part of the presentation(the part that goes to lazy and dumb kids if you've noticed). I'm shy and quiet and a little nerdy so i put up with them but i was hurt and it really pained me that they assumed that i was dumb. i have had similar experiences with kids who don't know me because they're not in my program. but i'm sure people of all races behave in weird ways when they are in a group. group dynamics is very complex in general. race just becomes another factor along with other parameters.
my advice to you:
a. success and hard work eventually pays off. don't suck on your thumb because one prof. doesn't like you. for all you know it has nothing to do with race. i've had professors who i thought didn't like me only to realize that they were rude to white students too. some profs. are just like a good chunk of humanity: socially awkward.
b. go to office hours. show that u love his/her class. after a while she'll know ur name and she'll find herself calling you. hopefully.
c. talk to other kids in your class about your observation and ask them to refer to you during discussions or something.
d. sometimes an awkward person is just an awkward person, not a racially biased person. sometimes you just need to go to the mall or movies and get into some vanities to give you perspective. the president is now black and he clearly doesn't care if people judge him on his race or not. pretend that race is never the issue. it helps to think outside your comfort zone even when your heart tells you u might be right.
e. if all fails, consider becoming an engineer or athlete. the numbers don't lie.