Factual error: It's established that the kids live in and go to school on the South Side (south of the Loop), and much is made of the fact that Malakai has nothing but his "respect" within his neighbourhood. At the movie's end, where Malakai wants Derek to accompany him on the robbery/murder, he tells Derek, "Meet me at 47th street, under the El." Yet when Derek runs off and jumps on the train to go meet Sara, we see him getting on a Brown Line train - those trains can only be found on the North side, miles and miles away from 47th street. In addition, his train is shown heading SOUTH toward the Loop, which means in order to be going that direction on that train he'd have rode on the train for about an hour, past the Loop entirely, then gotten off and turned back around toward the Loop again.
Factual error: At the beginning of the movie, Sara gets off the train and tells her father that she has two small bags and one big one, but she was riding a Metra train and you cannot check baggage on a Metra train.
Answer: "N*gro" was the PC term in the 60's. While by no means vulgar, it has mostly fallen out of use and some people are offended by it.
Grumpy Scot