From what you are telling me, your ECs are very impressive. I assume you would like to major in something like political science or the humanities, so your ECs definitely reflect that. However, I would recommend that you retake the ACT and SAT tests again, simply to improve your score. I understand that your score in one section may surpass all the rest, but your other scores are dragging your composite score down. Aim for 30+ on the ACT and 1300+ on the SAT to improve your chances. As for GPA, you may want to take some summer classes at a community college to improve your GPA AND show colleges that you are ready for college-level coursework in different subfields of your area of interest. Community colleges offer a wide selection of different course material, and you may even find yourself enjoying these classes!
That said, your ECs really stand out! Start working on your college essays as soon as possible so you can revise them enough that they are virtually perfect by the time you submit them. I would say you definitely have a good shot at getting into Wellesley if you follow a few of these tips. Good luck!
Chance me back here: http://talk.collegeconfidential.com/what-my-chances/1995754-chance-me-low-gpa-rank-cornell-rice-wash-u-ucla-etc.html#latest