DEAR HARRIETTE: I have been wearing my hair straight for many years, even though it is naturally curly. I’m now a student at a relatively conservative, mostly white school, and it may not seem like a big deal, but one way I fit in is by wearing my hair like my classmates. The other day we had a terrible, unexpected rainstorm. I got caught out in the rain, and, needless to say, my hair turned — it …