The problem is that the teacher/school probly thinks that because they are simply goldfish, that it doesn't matter. They fail to realise that even goldfish are animals and deserver to be treated much, much better than that.
You can actually call up the ASPCA and the school or even district could get in trouble... just tell the principal that the project is harming them and they are breaking moral and political rules.. and they could get in trouble..
not sure what kind of experiments they could actually be doing on them in 6th grade, although when I was in junior high we had a science teacher that would supposedly pour liquid nitrogen on a goldfish and then drop it on the floor where it would shatter....never saw it though, just heard about it.
I agree that if they're harming the fish its not good, but how come I never see any threads about folks outraged or wanting to rescue feeder fish from their LFS? It's always "I was in my lfs and saw this poor, mistreated <insert fish here> and took him home to save." What about the 600 goldfish stuffed in the 55 gallon tank with no future? Life is life...if folks are outraged about the mistreated oscars, bettas, etc. they should also be outraged about the feeders....Free the feeders!