Background: I started working at a franchise for a nationwide bakery chain 5 months ago. We are understaffed so on weekends and days off from school, most of us work about 8 hours. In the area I work, almost every other business hires at $15. All of my coworkers and I make about $10, and at least half of us are minors (including me). My coworkers and I are interested in collective bargaining with our manager to hopefully get a raise to $15, but we would be fine with $12. We have no idea how to get started or what to do when we would talk with our manager, so I am looking for any guidance or tips.
Edit: there are about 15 people at my location besides the manager. Also, all of our positions require us to stand for most of the time, and those baking/decorating the cakes to do so the entire time (besides break).