I have crossed swords with my old sparring partner, Squarepeg, on this issue more than once. What on Earth is an "English" school? One in which all of the staff are English? A school that follows the English National Curriculum, even though most of the students are Qataris and the staff are from Australia or South Africa? Or is it a school where the main medium of instruction is English, albeit that Arabic is the language of the playground?

"IB" stands for "International Baccalaureate". The I.B. is not an English invention and only a few school follow it.