Continuity mistake: In the final scene during the baseball game when Ray is batting he is wearing a hat, the angle changes when he starts running and his hat has disappeared.
Continuity mistake: Robyn celebrates her birthday in episode 12, and as she's in year 10, that would make her 15. However, when she runs away in episode 14, her age is said to be 14.
Character mistake: In episode 12 Robyn Stone celebrates her fifteenth birthday, but in this episode while she is in Mary's caravan watching the TV news report about her disappearance, the news reader gives her age as fourteen.
Continuity mistake: After Fran has read the diary page about herself she rushes off to the common room and is right behind Richard, Ray and Nick, but when she enters the common room, Richard, Ray and Nick are already inside sitting down.
Plot hole: Becky finds the photocopies of Natasha's diary pages in Nick's locker. They all fall out onto the floor as she opens the door, she picks them all up and puts them back inside the locker. Later on at home Becky is reading the diary page about herself - where did she get it from, when she put all the copies back into Nick's locker?
Continuity mistake: The final two episodes of this series are filmed in east Germany and are set in July. The snow on the ground comes and goes between scenes, plus why is it snowing in July?
Continuity mistake: When Arnie and Sam are following "animal man"'s blue van on their bikes down the busy road the vehicles on the road around the van change between shots.
Visible crew/equipment: When Mrs Keele drives her car at the racist political campaigner outside the school you can a reflection of the boom mike in the window of her car.
Continuity mistake: When Arnie is outside "Animal man's" flat on his bike there is another boy on a bike riding to his right. The angle changes to the entrance to the flats then back to Arnie, and the boy on the bike has disappeared.
Visible crew/equipment: Martha Jordan enters the room when Mr Robson is interviewing Brian about the assault on Jessica. As Brian leaves the room she walks towards Robson and a shadow of the camera and a sound man holding a boom mike can be seen on her green jacket.
Factual error: Justine and Maria are in Justine's bedroom. Justine is showing Maria the photos on her bedroom wall of her family and school friends. There is a photo of Banksie and Zammo on the wall. These two boys left Grange Hill at the end of series 10. Justine started in series 11, so she would not have known them.
Visible crew/equipment: In the girls changing room before the rugby match when Jessica and Paula are bickering, the shadow of a camera and its operator moving can be seen on the lockers.
Continuity mistake: When the helicopter descends there is a passenger in the front seat, but as it lands only the pilot is on board. And when Mr. Parrott approaches two men jump out of the back seat of the helicopter to "kidnap" him.
Visible crew/equipment: When Kevin and Wayne are in Kevin's bedroom there is a boom mike shadow on the wall.
Visible crew/equipment: When Sarah-Jane finds Poppy crying in the locker room, there is a boom mike shadow on Sarah-Jane's shirt when she sits down next to Poppy.
Continuity mistake: In some episodes Christophe's motorbike has French number plates and in others it has British number plates.
Continuity mistake: In the cafe when Gerald says his line "must dash got a deadline to meet on the school magazine" the same girl (with long brown hair) walks behind him twice within a few seconds.
Revealing mistake: Carlene makes Joanna a cup of coffee in the common room after finding her drunk in the toilet. Joanna refuses to drink it and drops the cup, breaking it - it's obvious that there was never any coffee in the cup.
Continuity mistake: In the first post titles scene Dill is running for the bus. There is a red car in front of the bus waiting to turn left, the camera cuts to Chris and when it cuts back to Dill the red car has gone and two more cars are in its place.
Visible crew/equipment: The camera lights are reflected in the side windows of Mr. Robson's car.
