Yes, I'm not a native speaker and not white, it could be one big reason they shortchange people like me. True too, my written english is not really good, worst at least, thus I try to avoid writing narratives as much as possible. I weathered the grammar part and survived and do have gotten my US National certification for Chemistry and AP Chem certification...thanks Chemistry has more numbers, equation and open ended inquiry than grammar. Now I'm back here in the US and getting back to teaching AP chemistry.
They hire teachers, real teachers, it's just a matter of how you define "real" is, but if your basis for real teaches are those with certification, there are few. But I don't question this, being a teacher is a learning and developing process, it's a profession that requires strategy on how you impart your knowledge to your student.
Again, pardon my grammar.

The Alchemist