Sam would have had her head shaved prior to her brain surgery.
Elvira Parker's padlock to her gate is facing the incorrect way.
When Paul tells his mom he is picking up the broken glass, his hands are holding the glass. In the next shot, his hands are not holding the glass.
When Samantha lifts the bully up, the wires holding him up can very faintly be seen.
When Elvira shoots BB the final time a cable is clearly visible attached to BB's undercarriage used to flip the robot backwards.
Paul's plan to rescue Samantha from the hospital is seriously flawed. A race against time before her life support system gets its plug pulled...? Outside, he's got an old VW minibus with which to transport a patient whose brain-dead body is being kept alive by a machine of which he would have had to pull the plug *anyway* before transporting to his laboratory what would then have been a corpse *anyway* whatever he did.
The furnace is ablaze, and the Pringle home almost burns down. Black smoke, rivaling a steam locomotive, billows out of the chimney, enough to cloud the sky. It s broad daylight, yet nobody noticed.