PP, free clinic, health department offers BC free to low cost.

How about planned parenthood?  BC is either free or really low cost.

Im a freshman in high school and i use project ruby for birth control (it is completely legal and safe) you can read more about it and its $20 a month 

If you feel you can have a reasonable conversation with your mom, ask her for help getting a prescription or possibly an IUD/implant.  The latter will probably be more cost-effective at your age, as they are good for several years once in, and very reliable.. You don't have to worry about forgetting a pill etc.  If you feel like the conversation will be positive, and you're not in danger, see if you can get coverage through their insurance. If not, and you feel like that conversation would go poorly, find another adult who you trust to help you.  If you don't have one, be sure to keep condoms on hand!  It'a not worth it risking an unplanned pregnancy or catching an std.  I'm not American but there might be something like a national help line for organizations like planned parenthood?  Maybe do a little research and see if there's somewhere you can call to help you track down resources for affordable options.

Birth control doesn't cost that much out of pocket. When I was on the pill it was just $27 a month. But my bf paid for half because we felt it is both of our responsibility.

IUD! It is the best thing since sliced bread! My partner and I are so glad I have it. 

Not sure where you live but in Oregon they have centers for human development in each big town that provides free birth control.