ralfy is correct. Teaching in the US is in demand. As far as I know, unless things have changed, a Pinoy cannot just go to the US and teach. They must become certified first. But, about 4-5 years ago a lot of inner cities were actively going into the Phls to find teachers to go to the US and teach. DC, NYC, Chicago, LA and a few other such places were a part of that.
But, a lot of teachers in the Phils can go to the US, get certified and legally teach in the US in at least some states.
This is sorta the way it is across most industries. The head doctor at a private hospital here in Catarman(the newest and best at that) was in the US for 25 years. He was never higher than a nurse manager. Basically the chief nurse in a Tampa Bay hospital. He said he could have taken about a year in classes and then the tests to be licensed and legally a doctor, but never wanted to do it and just kept his position in the nursing industry. From just a nurse in the US to performing surgeries and being head doctor of a private hospital in Phils.
Interesting side note. For those who watch news tv, Michelle Malkin, a political analyst, is pure filipina...at least her parents were both born and raised in the Phils. The moved to Philadelphia and did the extra schooling and went from being doctors in the Phils to doctors in the USA. Raised Michelle there and she went on to get the career she has now. So, some doctors in the Phils do take the extra schooling and become doctors in the USA.