This whole field trip is condescending for those students on a number of levels. Firstly, it is teaching them that their supposed "lack of achivement" is due to their dermal chromatics. Nothing can be further from the truth. 

That whole story is about, "You're a failure, kid, because you're Black." They learn that association, then they  learn "helplessness" because they need to be "helped out of" that situation. 

So, in fact, these kids are being taught learned helplessness, low self esteem, and to associate a  "gap" in their "failures" with their dermal chromatics IN RESPECT TO the dermal chromatics of others.

In effect, they are being taught to be racists.

I taught elementary public school for 31 years.  I found out that field trips are beloved by students, therefore beloved by parents.  Teachers hate field trips because they are a big headache to plan and execute.  Most of us who do take students on field trips do so because we believe in the value of them.  I have had parents of all ethnic groups tell me that their 6th grader never got to go on a field trip in 7 years of schooling.  I think this is terrible and should not be.  The problem could be solved by the school district designing field trips for each grade level that complement the curriculum.  That way, every child in the grade level would go on at least one field trip per school year.  That approach might have solved the field trip controversy in Ann Arbor.   

Of course today, with school funding cuts, field trip opportunities at least in Arizona have been cut drastically.

Tis racisim when whites exclude blacks, but tis not racisim when blacks exclude whites.

And the parents of these kids put up with this.