Debut -- Nightmares (Season 1)
Last Seen -- Same Episode
We first see Laura in the hallway. She's talking to a friend of hers, telling her she's going downstairs into the boiler room to sneak a smoke. When Billy Palmer sees what Laura's about to do, he whispers that she shouldn't go down there. Next thing we know, The Ugly Man comes out of the shadows to beat Laura. He keeps saying, "Lucky 19" and continues to beat the heck out of her.
When we see Laura next, she's in the hospital. Buffy and Giles have gone to visit her, and they ask her what happened. Buffy tells Laura that she can tell them anything, even if it sounds weird. So Laura is the person who lets them in on an important piece of information: her attacker said, "Lucky 19." This information is important later on when they find out who was responsible for beating Billy Palmer in the first place. Laura hasn't been seen since this episode. But it's probably safe to say that she gave up smoking. Or at the very least, sneaking smokes while at school!
Previous ABC Page
The ABCs of Sunnydale