I am a psychology teacher and have been thinking about looking for teaching opportunities in Thailand. I would like to teach IB psychology and am wondering how popular the International Baccalaureate is in Thailand.

If you have actual IB experience, you definitely have a better chance.

There are a few schools that offer it here. They are expensive and pay well. You must go through a recruiter like search associates or International School job fair to have a chance. Positions don't come very often. My last IB school didn't offer psychology as a subject though. They had 4-5 different science classes, Math, Humanities/ History, Business, Economics, Philosophy, TOK, Art(only 20 kids a year though) Language A and Language B.