The primary locations to apply for high school entrance exams in the United States are through the individual school districts or the schools themselves. Each district typically has its own set of requirements and deadlines for admission. To apply, students generally need to complete an application form, provide academic records, and sometimes take standardized tests like the ISEE or SSAT.

The application process varies widely depending on the school and district. For example, some private schools may require an interview or an essay as part of the application. Public schools, on the other hand, often focus on academic performance and standardized test scores. According to a report by the National Center for Education Statistics (NCES), in the 2017-2018 school year, approximately 85% of public high school students took at least one standardized test for college admissions or other purposes. This highlights the importance of standardized testing in the high school application process.

For private schools, the Independent School Admission Association of the United States (ISAAS) provides a comprehensive guide on how to apply. They recommend visiting the school's website for specific application procedures and deadlines. Additionally, the Common Application, a centralized application platform for college admissions, has expanded its services to include private high school applications. This platform streamlines the process for both students and schools, making it easier to apply to multiple schools simultaneously.

Public schools typically have their own application processes, which can be found on the district's website or by contacting the school directly. In some cases, students may need to apply through a centralized enrollment system, such as the OneApp system in New York City or the Open Enrollment system in Chicago. These systems allow students to apply to multiple schools within the district based on their preferences.

It's important to note that the application process for magnet schools, which offer specialized programs, may differ from traditional schools. Magnet schools often have specific admission criteria and may require additional applications or interviews. For instance, the magnet school application process in Los Angeles Unified School District involves a lottery system for admission.

In conclusion, the application process for high school entrance exams in the United States varies by school type and district. Students should research the specific requirements of each school they are interested in and follow the application procedures accordingly. The National Center for Education Statistics (NCES) and the Independent School Admission Association of the United States (ISAAS) provide valuable resources for navigating the application process.