@robbie21 - New Moon also uses the tension-building foreshadowing. Jacob sees his friends "change" in ways he doesn't understand before it happens to him.
It's not just in literature, of course. Movies and TV shows can be really helpful for teaching foreshadowing because people are more familiar with it and because it uses certain conventions that people are quick to pick up on. A woman's in the bathroom for too long? She's pregnant.