Congratulations, Lou Ann for your long Spanish writing.
Four weeks are a long time and don't forget that it'll be a total linguistic immersion. Don't think so much and act. Ask for a permission to your boss now (not tomorrow
), tell him that you haven't got your certification yet, and a year passes so quickly! I'd complain a bit: you don't have enough time to get it along the scholar year. Tell him that that would be a great advantage for you, since you have many Spanish speaker pupils and in this way you'll be able to have a better communication with them. You could offer to work some hours to make up (? I'm not sure, I want to say recuperar el tiempo que estés fuera
).
If you don't have your permission, ask GMU what problems there would be if you don't arrive in time. Maybe they can give you a summary or a guide about the course.
But I'm sure you'll be able to get your permission.
And don't forget your best smile.