High school, is a term primarily used in the United States and Canada to describe the level of education students receive from approximately 13 to 18 years old, although there is some variation. Most comparable to secondary schools, high schools generally deliver phase three of the ISCED model of education. High schools have subject-based classes. The name high school is applied in other countries, but no universal generalization can be made as to the age range, financial status, or ability level of the pupils accepted. In North America, most high schools include grades nine through twelve and students attend them following middle school (junior high school). 
The first institution labeled as a "high school" was Edinburgh's Royal High School in Scotland, which was founded in 1505. The Royal High School was used as a model for the first public high school in the United States, Boston Latin School, founded in Boston, Massachusetts in 1635.    Boston Latin School was initially a private school, so although it did become the first public high school, a school system in Dedham, Massachusetts was the first to be supported by public taxation.  The schools prepared boys for the law or the church. The length of the school day varied with the seasons, but there was a shortage of Latin speakers available to become teachers because the job was unattractive due to low status and low pay. The colony ordered in the English Protestant Tutor, retitled as The New England Primer, to be used as a textbook, and the tuition was written by and had a Calvinist tone.  This was the start of a secondary education system.
In 1642, the Massachusetts Bay Colony was able to pass a law to require parents to make sure that their children were able to read, which required some form of elementary education. In 1647, Massachusetts again passed a law that required communities to establish some type of public schooling system. Elementary schools were to be formed in every town with 50 or more families, and every town with at least 100 families would have to provide a Latin Grammar School.  
Over a century later in 1779, Thomas Jefferson proposed the opening of new secondary schools to provide segregated secondary schools with different tracks in his words for "the laboring(sick) and the learned." The new academies would be practical in nature but allow a few of the working class to advance by "raking a few geniuses from the rubbish." At this time, the colonies were planning to break away from Lord North government in Britain, and working up a constitution which would define the white colonists' freedoms and rights. In November 1783, the American colonies stood on their own.
In 1785, before the U.S. Constitution was ratified, the Continental Congress passed a law calling for a survey of the "Northwest Territory" which included what was to become the state of Ohio. The law created "townships", reserving a portion of each township for a local school.  Under the constitution, education was devolved to individual states.
The Pennsylvania state constitution, written in 1790, calls for free public education, but only for poor children, assuming that the rich will pay for their own children's schooling.  In 1805, the New York Public School Society was formed by the wealthy to provide education to the poor. These schools were run on the Lancasterian system, in which one "master" taught hundreds of students in a single room. The masters would give wrote lessons to the older students, who would then pass it down to the younger students. Society was moving from an agrarian model with small independent plots to an industrial one, where workers needed to be literate and numerate. Lancastrian schools emphasized discipline and obedience: qualities that factory owners needed in their workers. 
An 1817 Boston Town Meeting petitioned for the establishment of a system of free public primary schools. The main support came from local merchants, businessmen, and wealthier artisans, while many wage earners opposed it because they knew they would be paying for it through income taxation. In spite of this, Boston Latin School became public in 1820. This was the first public high school in the United States. Seven years later, a state law in Massachusetts made all grades of public school open to all pupils, free of charge. 
However, in the slave-owning states, things were different. Even after public schools were being opened up to all ages in Massachusetts, in the 1830s, it was illegal in southern states to teach black children to read. High schools were out of the question.  After many years of advocacy, in 1957, federal court ordered the integration of Little Rock, Arkansas public schools. The governor sent in troops to physically prevent nine African American students from enrolling at all-white Central High School. Though, this decision was overturned by the president. The same delay in equality in public high schools can be accounted for the general regarding of other groups as minorities in the US. 
While there is no set standard for American high schools, some generalizations can be made about the majority. Schools are managed by local, elected school districts. There is a range in quality from basic education to more intellectually-stimulating environments for students aged approximately 13 to 18 years of age. 
Pupils (students) enter at the age of 13 or 14 and pass through four years:
- Freshman ( ninth grade ; the equivalent of year 10 in the British System)
- Sophomore ( tenth grade; the equivalent of year 11 in the British System)
- Junior ( eleventh grade; the equivalent of year 12 in the British System)
- Senior (twelfth grade; the equivalent of year 13 in the British System)
School years are normally around nine months long (from August or September to May or June), and are broken up into quarters or semesters.  College entry is controlled by many factors including Grade Point Average (GPA), and an elective SAT or ACT exam run by two non-profit organizations: the College Board and the ACT, respectively.
Smaller schools can educate less than 200 pupils total, while some teach over 4000 at any given time. 
The typical high school day includes:
- Students arriving between seven and nine in the morning and leaving school between two and four in the afternoon.
- Four to eight 45 to 90 minute class periods, broken up by around five minutes to get to the next class (schools may hold classes daily for a shorter time (traditional scheduling) or alternate days for an extended session ( block scheduling)).
- A lunch break (some schools permit students to leave campus to eat, though most hold lunches on-site). 
- Homework amount differs depending on the school's purpose and culture.
- Extracurricular sports team activities right after school (sometimes track, field, and swim sports hold practices in the early morning before the school day starts) (the better the school district the larger the variety of extracurricular clubs and activities offered). 
The high school's emphasis determined by the community and school district (is):
- general education
- high-achieving college prep (ex. Advanced Placement (AP))
- speciality such as arts, music, theatre, STEM (science, technology, engineering and mathematics)
- mixed purpose 
A high school curriculum is defined in terms of Carnegie Units, which approximate to 120 class contact hours within a year. This is one hour a day, five days a week for twenty-four weeks. Students who satisfactorily complete a unit are awarded a credit.  No two schools will be the same, and no two students will have the same classes, there are some general principles, however. Students can also be on different programs within the same school with Advanced/Honors, CP (College Preparatory), AP ( Advanced Placement), and IB ( International Baccalaureate) classes.
Students typically do four years of study, with eight core subjects and electives, both of which vary by school. Passing a course earns credit and students must earn at least 30 credits to graduate, among other requirements. Study halls are sometimes offered, which don't contribute to GPA or number of credits earned. 
2014 recommended federal standards for Physical Education are at least 225 minutes of P.E. week for middle school and high school. The standards involve:
- Competency in motor skills and movement patterns,
- Understanding of movement concepts,
- Regular participation in physical activity,
- Achievement and maintenance of health‐related fitness,
- Responsible behavior in physical activity settings, and
- Value of physical activity. 
Amenities, experiences, extracurriculars, and breadth of available courses is dependent on funding. This is made up of:
- A fixed per-capita sum from the state,
- Collection of property taxes within the school district,
- Federal government grants for special programs,
- Federal seedcorn funding to encourage cooperation with the federal Department of Education,
- Parental volunteerism,
- Parental fundraising,
- Federally subsidized lunch and breakfast for schools with high number of low-income students. 
High schools are depicted in many teenage-orientated films and television soap operas. Almost universally, these films fall into the comedy or social issues/drama genre categories.
Due to Californian labor laws, the actors used are young adults, who rarely look young and can no longer act like adolescents. Hollywood fails to demonstrate the insularity of High School life where the pupil assumes everything revolves around them. Since sex between even alleged teenagers runs the risk of being considered child pornography, teenage sex, pregnancy, and STDs are barely covered and then only indirectly. High school films from Hollywood rarely discuss the economic disparities between the social classes where the poor gravitate to the lower esteemed courses. 
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- James J. Trotter, The Royal High School, Edinburgh (London: Sir Isaac Pitman & Sons, 1911), p. 186.
- J. B. Barclay, The Tounis Scule: The Royal High School of Edinburgh (Edinburgh: Royal High School Club, 1974), p. 137.
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- College Board, SAT, 2017
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- Iowa Chiro Clinic, 2014
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