School life

I've been thinking of switching out of school. I'm not bullied or anything but I want a new change. Not completely committed tho. Reason/back story: I have a friend group of only us three and we are good friends but we hang out with a bigger group of about 20. I know a few of them but we are not close with them as my two other friends so when they do anything they will always invite my two friends and leave me behind. Always feeling left out I would go to my other friends in different groups. However usually they have at least one person in that group that does not approve/accept me. I'm lost.