Amazing,!  This is a very serious problem we are facing now.  We are in a situation " middle of nowhere".  Neither we can accept the situation which makes our kids American nor we can keep our kids away from their surroundings.   The main thing is you are the one who worries about your kids the most.   If we can somehow make our kids proud of being different than others (Especially being a Nepali), that would probably address this problem to some extent.  I don't think sending a 8-year boy to a boarding school back home is a right solution.  You are the one who can teach your kids the best.  I have seen lots of parents enjoying more when their kids forget their native language.