What qualifies as leadership experience

I find my resume mostly lacks leadership experience. What qualifies as leadership experience and in what unique ways could I obtain some (it's not just for the resume; I would genuinely like some for myself)? Something other than clubs at school and sports teams.. Mind you, they do give VP positions to pretty much everyone at the finance club lol. If I'm always doing all the work for all my team members in school and participate a ton in class, for instance, is there any way to convey that or should I even mention it?

Thanks