What is / are the officially / generally used text books used to teach English to students in Thailand?

I would like the name of the series in English script, if possible

Thank you, good people!

I teach at many govt. schools. They are all different. It is up to the local school officials. Expressions and Zoom series are used the most. I cannot answer your question if there is an official guideline and list of books to buy.

Sometimes, it us how much the local scholastic and other publishing companies offer tea money to the local folk.