How does high school work in america?

Every high school has their own requirements to graduate. An amount of credits needed and certain classes must be taken.
Usually-4 years of English, 3 of math, 3 of science, 2 of history, gym class, health class plus electives.
Most students take chemistry- but one may take it in 10th grade, while another may take it in 12 grade. Every class has a different group of students. they can be from different grades. English classes usually have students from the same grade in them.
Many students take 2/3 years of a foreign language since most universities require it to apply. There is band, orchestra, choir, and theater. And elective core subjects like calculus and physics

U no, from other answer, I prefer English high school... Lucky, really, since we're here 4 longer!

In America you have a group of students who are your same age who are considered your "class", but you can choose your own classes, so you probably won't have the same classes with most of your "class."