When Dorothy goes into her office and locks Patsy out, there is a table outside the door on which four books are resting. In the next shot, a closeup of the table top, there are only two books.
When Thompson is brought to trial by the boys in their court for the murder of Johnny, a white handkerchief is visible in the breast pocket of his black suit coat in the medium close-ups. In the long shots, the handkerchief is missing.
On the boys' first night at the school, there are two shots of Jimmy in the dormitory in which his hair (in the area above his ears) is longer than in any of the other shots.
When Thompson falls on the barbwire fence after jumping from the burning barn, it is clearly a dummy.
When he enters the reformatory, Skinny is diagnosed as having lung trouble and recommended for segregation. Yet this never happens--leading to his death from exposure.
At the hearing, the judge asks Jimmy's parents why, in the past year, he suddenly went from being a good student to a very poor one. The parents say they don't know, and Jimmy looks sullen. The judge does not ask Jimmy himself. This seems to be a set-up for the revelation of some trauma. But the matter is never referred to again.
At the start of the court room scene, when the first kid (Anthony Carmonatti?) is called before the judge, the boom briefly enters the upper right corner of the picture.
When Patsy is talking to Jimmy in the boy's courtroom, Jimmy sketches a guard's face. While he is doing this, the shadow of the boom can be seen moving across the wall in the upper left hand corner of the screen. Then when Patsy is coaxing Jimmy to draw him, the shadow of the boom can be seen moving across the wall in the upper left hand corner of the screen again.