Factual error: The Sanderson House had been turned into a museum complete with a gift counter. The museum had been closed for years (note the dust and spider webs). The fluid in the lighter max gets would have evaporated after a few months as Zippos are not airtight like a plastic disposable lighter would be.
Continuity mistake: When Max and Allison rescue Dani from the witches' house, they turn on the car lights to trick the witches into thinking it is daylight. After they get in the car and drive off, the same light that was supposed to have come from the headlight is still shining after they have left.
Factual error: Binx is shown pouring hot liquid from a cauldron that is over a flame, the iron would be too hot for him to touch without getting burned.
Continuity mistake: When Winifred turns to stone in the graveyard, her fingernails rip shreds of cloth off of Max's sweatshirt (you can see them when he falls). Exactly one minute later, when he is lying down next to Dani and talking to her, it is clear that his sweatshirt is merely ripped, not shredded.
Factual error: Just after the towns-people have hung the three witches, you can see the executioner walking away. The outfit he is wearing is leather and has some sort of metal spikes on it. This outfit is too modern for that particular time.
Continuity mistake: When the witches take Dani back to the museum, the rope they use to tie her up with changes from shot to shot. First it's up around her neck, then it's around her chest.
Continuity mistake: When the Sanderson sisters get on the bus, the headlights on the bus are on because it is dark out. They are visibly on at that point and as well as when the bus runs over Binx but, when the sisters get off of the bus, the lights are not on (it is still dark out and it is only a few minutes later). If the bus was merely letting them off (which it was, it drove away a few seconds later), why were the lights turned off?