Unhelpful High School Teacher

How not? The NYT agrees with the unhelpful teacher:

'Note: People who are Hispanic are defined as those from Spanish or Portuguese culture or origin regardless of race': https://nyti.ms/2Zt4Xad (footnote)

Yet Hispanic people are seen as non-white ('regardless of race'). Add that, for the NYT, Portuguese are seen as Hispanic regardless of history. In short, 'Hispanic' is both a race and not.

I don't know, maybe Germans might be defined as Chinese or vice versa, and the NYT as a crazier supplement of Mad.

Uh no, you could be Ukrainian or a Czech, or a German or a Polack. If you go by race instead of skin color there are even more possibilities including most Turks, central and South Americans, and so many more.

Yes, no need to say you're right, of course. It's the teacher who is wrong, and so many people who agree with her. It is only a meme.