it's always fun to poke fun at my little brother's friends.... but here it goes
first a little explainin: Harmon Hall is amongst Mexico's most prestigious language institutes, I worked there for 8 years and they had us teachers on continuous training and updating, we had to score over 600 points on TOEFL exams they'd apply every six months, so as to to maintain QC certification standards, so take it from me, it's a very good school, and I personally made more than a few people bilingual, so I do advice you take courses there, heck, my wife is teaching there
now to your teaching project
as a Texas Certified Bilingual Social Studies teacher from 8th to 12th grade, lemme tell you a little bit about the Valley's school districts' policies on foreign teachers:
several years ago, the Rio Grande Valley area (which borders with the town we live in) had an all time shortage of teachers, so they opened applications for Mexican teachers, the only condition is that you had to learn English or be bilingual.
thing is, that unlike the US, here in Mexico, Pedagogy is a bona fide and very popular career choice, given the Federalized basic school system, teachers here are thoroughly trained in the latest pedagogical tools and approaches... hence we've got some very good teachers here... and some that suck, but that's a given in any area
this outsourcing program lured some of the finest talents in the area to the RGV's school districts, where they just had to revalidate their college curriculum or something like that, and take a pedagogy course, in which they all excelled and a subsequent specialty test, which most of us aced.
the problem began when these newly certified teachers, who were given a one year internship before giving them a full time position, started getting their positions before the year was up, some of them even rose to administration positions in months, to the general displeasure of some native teachers who had been waiting for years for such positions
guess what happened? as soon as enough of those not-so-happy people got promotions they changed the standards so that if Mexican teachers wanted to apply in their school districts, they'd just deny them work visa permits and send them over to other ISDs in the Houston, Dallas and San Antonio areas, getting to an "if you want a job, you're not getting it here" kinda of policy
hence, the latter comers to these certifications, such as myself, were barred from getting a teaching job across the border, although I still get calls and emails from ISD's in Bexar county, Houston and the like to get me to work there, but alas, they won't take my family with me. so in my case is a no go
what I would advice here is get better at the language and apply, you might get offers where you'd have to move from here, but it will be worth it
and please, DO GET BETTER AT IT, it's been 5 years and your skills have not improved much, and this is not an insult or an attack, I'm just telling you as someone with 14 years of experience teaching the language: you've got a lot of work to do, but nothing you can't achieve
so there you have it