My mother is overprotective?

Ok im 14 and my mom neva lets me like go hang wit my friends. like on mondays and fridays i am free afta skool and my parents are so strict wit me goin out wit my friends. i think its cuz they dont want me to grow up. i live like 3 blocks from my skool and they also let me walk home but thts only if some one cant pick me up. what do i tell them to convinve them to let me go out more. also theirs this birthday party tht i wanna go to but i dont have a ride but my friend offered me a ride. how do i get her ( my mom ) to go wit it