I’m a rising high school junior living in a third world Asian country (though am rather middle-class myself) and am about to transfer to an international school in my country (so I’m starting from scratch with my ECs). What can I do to improve my ECs? And would you say they’re strong enough, given that I’m aiming to attend one of the best math/engineering-oriented US universities one day? Stanford’s the dream. 
Notable credentials:
-country’s equivalent to MOSP/MOP (am part of the top 20 IMO pool… but not sure if I’ll pursue making the team)
-bronze at China Girls Math Olympiad
-won some regional & interscholastic math, chem. meets
-youngest-ever news editor of school paper
-student council treasury staff- designed our official school hoodie and eco-bag
-published a research paper (as a school requirement) & it ranked top 8 in some national research fair
-Gov’t. Youth Excellence in Science Awardee
-monthly volunteer work, have raised some funds (< $1000) for school scholarship foundation with fair booths, etc.
Plans:
-apply to Google Science Fair (the only prestigious fair open internationally)… unsure if my research will qualify
-??? don’t know what else to do, idk what to do this summer
As a non-US resident, I’m quite worried since a lot of the credentials I’ve listed are probably only locally known, so US schools might have no idea how small/big these contests are… I haven’t pursued anything on an international scale, and I’m really frustrated since I’ve also looked into applying for RSI, Intel, etc. only to find out that they’re open to just US citizens.
At this rate, do I stand a good chance applying for the top-tier schools (Ivies, MIT, Stanford)? And what else would you guys recommend I do to really solidify my ECs?