I was taught (and therefore teach my kids) that if you wanted to say: pasar el tiempo, you should use, spend time
but I've seen in many books recently: pass the time
is it a new usage? when I learnt English it was considered a terrible mistake!
i understand "to spend time" as the way in which one makes use of his/her time, while it is the time which passes. at the same time you can pass the time doing anything, like "what to do to pass the time while you're waiting",