Hi there,
Thanks for your post and for all of the detailed info into your profile, experience, and situation. You have a lot of great experiences to draw from, and schools are often interested in non-traditional candidates who have a lot to contribute to the class, as long as you've demonstrated that you can handle the quantitative side and academic rigor of b-school, and that you can speak to your goals and why the MBA is right for you, both of which it appears you will be able to address without a problem based on the info here.
You have a lot of great leadership experiences, accomplishments, and international experience as well, and can certainly speak to mentoring and influencing others, as well as strong communication skills, through your teaching and all that you've led, initiated, and managed over the years. You also seem to have done your research and to be fairly self-aware which can help in the admissions process, and in your essays and interviews.
As for schools, HBS, Darden & Kellogg certainly seem like good matches for you. Stanford definitely comes to mind, I know you mentioned that one as well, though keep in mind that Stanford is one of the most selective programs out there. I would think you'd have a good chance at Duke or UCLA, possibly Haas and Darden as well, with Kellogg, HBS, and Stanford still being challenging given all of the competitive applicants that apply (in increasing order). So some of it depends on which programs you are most passionate about. (For more about choosing schools, you are welcome to check out our free download at:
https://info.mbamission.com/Selecting-Yo ... ram-E-Book. Columbia is another program that comes to mind based on your background.
Don't underestimate the importance of the application essays.... that is where you really demonstrate who you are; what makes you unique; what you'll bring to the program; what you'll do with the degree; why that program is a great fit for you. Be sure to invest a lot of time and energy into compelling essays that make the case for you.
Please let us know if you have further questions, and wishing you the best!