Practicing Awareness of Microaggressions

I work in a school with about fifty percent Hispanic students and the other half being pretty equally distributed between African-American and White students.  There is a small amount of other populations, such as Asian, Pacific-Islander, and Native American.  Since learning about microagressions this week, I have been paying attention to the conversations between students.  I have realized that MANY microagressions occur on a daily basis.  For example, I am frequently referred to as being 'so white.'  I am not quite sure what the students mean by this, but I am fairly certain that they are probably calling me a dork.  To me, the implication is that white people aren't cool.  They are nerdy and no fun.  I do have a good sense of humor so it really doesn't bother me.  In fact, I am nerdy and dorky.  However, these microaggressions aren't always said in a good natured and joking fashion.  I frequently hear the students use the term 'ghetto' to describe other students.  It is obvious this is a derogatory term meant to marginalize the person they are talking about. 

After reviewing the week's resources Monday night, I went to bed thinking about all the times I have participated in or witnessed microagressions.  I set out Tuesday to seek out instances of microaggressions for this assignment.  I didn't have to wait long as the student who was doing the announcements signed off with "have a taco Tuesday" in a very exaggerated Hispanic accent.  One of my white students immediately proclaimed that is was a racist comment.  Although I did not say anything out loud, I also felt the comment was inappropriate.  Several of the students in the class got into a discussion about the topic.  Some of the students thought it was insensitive while others thought it is was funny.  Many of them felt that it wasn't racist since the boy who said it is Hispanic.  Many of the same students thought it would have been racist for a white person to have said the same thing.  These statements lead into a lengthy class discussion.  One good point that was brought up by the students is the use of the 'N' word.  Many African-American students use the word with their friends, but are offended when a person who is not black uses it.  To me the term is derogatory no matter who uses it.  I am correct in my thinking?