Theory:Doctor Who television discontinuity and plot holes/School Reunion


 * When Mr. Wagner tells Luke that he has extra class, he is followed by Melissa, not Luke.
 * Luke may have been Melissa's last name. Whether he said Melissa or Luke, she would have followed.
 * Melissa may have been going somewhere else, and another person called Luke followed him soon after. Plus the boy's name is Kenny not Luke


 * At the start Lassar assumes bat form to devour a child. He later tells the Doctor that while his brothers remain in bat form, with a morphic illusion giving them the appearance of Humans, his own Human form is real, a personal preference.
 * There may have been a second Krillitane in the room. After he closes the door, we lose sight of him. A moment later, the shadow bat-like image is seen through the small window. It cannot be clearly stated whether he transformed into the image, or if it was another Krillitane already in the room.
 * His own human form may have been real, but he may have retained the ability to transform back to bat form at will.


 * If Sarah Jane was investigating the school, like the Doctor, to discover what was going on after the lights and all the staff being replaced, why was she so openly asking question to the Doctor under his guise as "John Smith". If the staff are all being replaced recently surely meeting a stranger, with an ambiguously genuine name, who had only just started also would ring some alarm bells, yet she very openly starts asking questions suspiciously having only just been totally sycophantic to Mr. Finch.
 * As indicated, this is because he is brand new and presumably therefore less likely to be part of any conspiracy surrounding the headmaster.
 * Sarah Jane always confronts aliens whenever she meets them as seen in The Sarah Jane Adventures.


 * It is very unlikely that hundreds of papers would be flying out after the school blew up, especially ones that are not burnt.
 * It is quite likely that the heat of the explosion in one area of the school would cause papers in other parts of the building to blow out the windows.


 * How can what appears to be a state school introduce a new curriculum when all state schools have to follow the national curriculum?
 * Exceptions to the rules always exist.
 * On the surface, the school may appear to be following the national curriculum, but may not actually.


 * Why don't the dinner ladies just put a proper lid on the oil barrel before moving it?
 * The oil may have required ventilation.


 * Why does Sarah Jane have K9 in her car, given that he's non-functional to the extent that the Doctor takes an hour to repair him enough to switch him on.
 * She was waiting for the Doctor to return.
 * She may have taken him along a bit like a security blanket type thing - making her feel more like the Doctor.
 * If he suddenly switched off one day, it is possible he may have switched on another. If she was in danger and he was not with her, but was working, he would have been no use.


 * Why was K9 in the car rather than the boot the next day when he wasn't even switched on?
 * He may have been switched on, simply in an un-activated mode. He was damaged and not 100% working so he was probably flicking on and off, and plus his batteries weren't fully charged


 * Why does unplugging it from the current cause the router to explode?
 * The router may be of alien technology, given that the program used to crack the code seems alien. Alien devices may work differently.


 * How come Sarah Jane doesn't have her sonic lipstick or scanner watch which are gifts from the Doctor; we don't see the Doctor give them to her at the end of the episode, they aren't attached to K-9 in anyway and Sarah Jane would have mentioned the Doctor visiting again in Invasion of the Bane
 * Maybe because he gives them to her off screen that we don't see, my best guess, either that or a production fail.

Most likely reason is either the Doctor can't count or this is another production error.
 * The Doctor specifies that he had regenerated "half a dozen" times since he last met her. This would be true only if the Fourth Doctor was the last Doctor she met. However, he met her in his Fifth (DW: The Five Doctors), Seventh (DWM: Train-Flight, PDA: Bullet Time), and Eighth incarnations (EDA: Interference - Book One, EDA: Interference - Book Two). Although the Eighth Doctor adventure seems to have been overwritten, her meetings with the Seventh and Fifth have not, and the Doctor has only regenerated three times (a quarter dozen) since he last canonically met her.

Maybe the TARDIS is set to materialise away from an explosion or similar, it won't have got damaged as in the episode 'The Parting Of The Ways' when the Dalek rockets hit the Tardis and when the Daleks shoot the TARDIS on board the Emperor's Ship it had extrapolator shielding from Margaret's (slitheen) technology in Boom Town it would have got protected again when the school exploded.
 * In the beginning of the episode, the TARDIS is in the school. The Doctor was going to go back in and get it to analyse the oil, but Sarah Jane mentions that she has K9 in the car, so they go to the car instead. At the end of the episode, the TARDIS is outside on a sunny day. Wouldn't the TARDIS have blown up in the explosion since we never see them go back to get it?

the tardis can withstand great ammounts of heat without scorching. also, the tardis might have been moved by the doctor before the final scene.