Setting: US (New England area--small but fairly liberal town), contemporary
I'm working on a story with two teen girl main characters who were once close friends and are now enemies. One is popular and the other doesn't care at all about social status but is involved in sports and a few extracurriculars. If the popular one wanted to start a rumor to ruin the other girl's rep, what kinds of rumors might she start? I'm SO out of touch with teen life today. I feel like back teens are so much crueler now than they were when I was in high school and I can't drum up anything awful enough!
I've done my best to google, using terms like rumor + enemy + high school, and ruined reputation and the like, in all kinds of configurations, but no surprise, no one is exactly documenting this kind of thing.
ETA: I'd prefer to avoid the lesbian/slut option if possible. Getting into why would be complicated to explain without going into my whole plot, but they don't quite work for what I'm going for. I also want to avoid hard-drug-related rumors. Just about anything else is workable. And I do know that it's likely that people won't believe the rumors 100%, I just need enough to get people talking about her and making her uncomfortable in school for a few weeks.
Edited again: Thanks guys! I think I have what I need. You've all given me some great ideas and pointed out some factors that I might have otherwise overlooked. Everyone's input has been very much appreciated!