Some characters can be seen missing from their desks and others appear to be wearing different clothes in other shots.
Once the Girl is done gathering all her things, she grabs them with her left hand but in the next shot they're in her right hand.
When the Girl exits the class, no notebook or papers are seen. But a few shots later, those exact objects are in her hands.
The time cards read about early afternoon but the clock on the wall in the class reads at about 3:30 in the afternoon.
The building that the Girl enters clearly says communication, yet the text book she brings out is clearly a math text book.