You are correct in that the main weakness in your application based on the information you shared here would be your GPA; but other than that I believe you actually have a fairly strong profile for the programs you have mentioned, as long as the rest of your application is strong as well--mainly essays, recommendations, resume and interview.
The examples you mentioned of volunteer tutoring as well as the website you started sound genuine and interesting, and demonstrate your initiative, determination, project management skills and also your willingness to help others and the community, all of which are important to showcase as they indicate that you will bring those same traits to business school.
Your goals make sense so far which is important, and your school list sounds appropriate, with Booth and Stern being the most competitive of the list. While your GPA is low, that can be balanced with the high GMAT and strong work experience, and your explanation of the struggles with the GPA also makes sense.
I encourage you to be sure to dedicate sufficient time to essays preparation beginning now and through the summer, because with an outstanding set of essays you should have fairly good chances at the programs you mentioned. In your essays you want to demonstrate both what you will bring to the program, and also what the program will do for you and your career. And you want to tailor your essays and applications to each school, providing specific reasons why that is the right program for you and showing a good fit between you and the school.
Please keep us posted on other questions and how everything goes! Good luck to you.
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