Collect pictures from past students that have gone on to have successful careers. Post them around the school halls. It would stand to encourage the current students and give them ideas of what they might want to do when they graduate. They would see pictures of former students who are now doctors, lawyers, managers, teachers, etc...
Some kids tend to just go to school and go home, day after day. They have no idea what they want to do in the future. As parents, we want our kids to be kids. At the same time, we know that reality is that time flies and they won't be kids long. So they need to keep in the back of their mind what they might want to do when they get older. It doesn't mean they can't change their mind, it just gets them thinking about it.