Does the teacher in Langston Hughes' "Theme for English B" appear to be racist?

No, the teacher in Hughes's "Theme for English B" does not appear to be racist. Rather, the professor at Columbia ("this college on the hill above Harlem") where the speaker is the "only colored student in my class" is most likely not acquainted with the African-American culture below the hill in Harlem, where he lives. Still, he wonders if his racial difference will "color" the professor's perspective of him and cause him to be judged differently from the others in the class.

Langston Hughes himself attended Columbia University for one year: 1921-1922. As a freshman he and his white classmates were assigned an autobiographical theme that he writes about in his poem. There were millions of Caucasian people who were not acquainted with other races, especially in the Northern states, most of which had been free states (no slavery) before the Civil War.

Therefore, when the speaker writes,

But I guess I'm what
I feel and see and hear, Harlem, I hear you...

he describes how his distinctive environment is a part of him. Yet he is human, just as are all his classmates; he enjoys similar things that they do, although with some different tastes in music:

Well, I like to eat, sleep, drink, and be in love.
I like to work, read, learn, and understand life.
I like a pipe for a Christmas present,
or records--Bessie [Smith], bop, or Bach.

Still, the speaker of Hughes's poem wonders if he will be perceived as "colored." That is, he wonders if he will be judged as "different," or even "just not quite the same" as the other students. He wonders if his instructor will think of him as inferior, perhaps, not because the professor is "racist," but simply because the professor does not understand the speaker and where he comes from.

I guess being colored doesn't make me not like
the same things other folks like who are other races.
So will my page be colored that I write?

The last line hints of skepticism. Will the teacher think of what he writes as different from the others students simply because he is "colored"? Or will the teacher evaluate him, just as the others will be, simply on the content of what is written?