I am a US citizen with a Thai wife of 16 years. She has been to the US twice, in 2005 and 2011. Her previous tourist visa expired and she was twice refused a new one. Officials refused to even look at the mountain of paperwork we provided on the second try. We have a daughter, raised here, now living there with my sister. No explanations, no apologies...nothing. An absolute disgrace.
It's no guarantee you can get her into the country on a tourist visa, though. Mine visited twice in 2005 and 2011. We reapplied twice during the Trump administration and were rejected both times without explanation. Our daughter now lives in the States, but her mother can't go to her high school graduation. I am so disgusted with them.
My wife of 17 years was denied tourist visas twice during the Trump administration despite having visited twice before under a previous tourist visa. A so-called agent told me that during the Trump administration they changed the policy. I don't know if it's been changed since.
My wife of 17 years, who had been to the US twice already under a previous visa, was then denied another tourist visa twice during the Trump administration. No reason given.
I have done this and it works quite well in terms of visas...we just run it as a school, not a business. Ours is in the sticks of Songkhla, so it's a real niche market...but there is no real competition. Since you're wife is a teacher that should help immensely in dealing with all the required paperwork.