Thanks for posting, and GREAT JOB on the 770 GMAT!! Top 1% of test takers, that is no small feat.
The strengths of your profile based on this info are:
-international (?-- was that IN Vietnam if I'm understanding correctly?) experience
-teaching experience can be translated to showing strong communication and leadership skills
-less common/non-traditional background (can be a plus or a minus; if really emphasize how you'll have a unique viewpoint in the classroom, can be a plus)
-less common nationality
Potential weaknesses or challenges
-3.0 GPA (so... probably good thing that you rocked that 770!)
-less common background-- just spend some time brainstorming about ANY ways you've shown leadership, either in or out of the workplace, to address any concerns there
-goals need to be solidified (as you mentioned)
As for schools, you probably know that Stanford is practically THE toughest school to get into, partly due to the smaller class size than even say HBS, so will definitely not be easy. But they do also have a lot of ties to education there, so there may be a good fit, if that is part of what draws you to them. From your list Fuqua and Tuck would be most reasonable/better chances to get in. It's up to you how far you want to go with adding safety schools; certainly yes I think you would get in at UNC and Mendoza (as long as essays and rest of apps are solid). Think some about each school, and imagine if you got in NO WHERE ELSE... what would you do? Would you still go? Would you rather wait and re-apply? Etc, and only apply to schools you would definitely consider going to.
Overall you do have a lot going for you and some of it will come down to how you showcase who you are in the essays, and how you lay out that story of WHY you want this MBA and what you'll do with it.
Happy to help further in any way shape or form, just let us know. Good luck to you!
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