how stupid
when the kids are in the swimming pool and the alien arrives, they run into the school instead of out the door they came in where their cars are! ridiculous!
All right, that's it! No more Mr. Nice Gaius!
It makes perfect sense. The school offers them a covered, circuitous route to (possibly) safety; running out the door would take them towards their cars, but also take them totally out into the open. Being panicked and confused, they likely didn't know where the danger was coming from, or how much more of it there was, so they instinctively went for the covered route.
'Then' and 'than' are completely different words and have completely different meanings.