High school students are divided by grades. It begins at 9th grade and finishes with 12th grade. Some high schools, even public high schools, have admission exams or an application process. Public schools admit students based on where they live. In order to successfully complete high school, students have to complete a series of core classes including math, High schools classes are designed to prepare students for college. Some high schools offer specialized skills so that students can find work after graduation without going to college. Those are called vocational high schools. In high school, some students have the opportunity to take Advanced Placement (AP) classes. These are college level classes. If the students pass an exam after taking AP classes, they can get college credit. In high school, students move from class to class throughout the school day.