Okay! Well American school is separated into three sections. Elementary school, Middle school, and High school. In elementary school, education is restricted into 6 levels, and sometimes 7. From kindergarten, then to 1st grade through 5th grade/6th grade. Elementary school is one school you attend through that duration. After elementary school, you go to middle school and that takes place for 2-3 years, 6th grade/7th grade through 8th grade. Middle school allows the chance for accelerated classes, and you can skip levels of math in them as well, like taking Algebra when in 6th,7th,8th grade. High school allows you to take larger amounts of varying classes too. All sorts of science classes like chemistry, physics, biology can be taken as a 9th grader. And math ranging from Algebra all the way to Calculus is available as well. It's is not a private school, and is free for any student. There are schools for different religions that offer their education for their students, combining religion with lessons. And some prepare for certain colleges, but are very expensive. My school doesn't offer a lot of expense, only for clubs your interested in and fundraisers. Schools where you don't pay is called Public school here. Education in America is very different from other countries! What about the study of students in Thailand