Education in the United States is free and compulsory for 0 years, beginning at age and culminating at age 16

Compulsory Education in the U.S. (Elementary School and Secondary School)

Elementary Education
Texas school childrenElementary or primary education in the United States typically begins at age six and represents the beginning of a student’s compulsory education. This stage of education lasts six years, beginning with grade one and culminating with grade 6 (age 12). The length of the school day for elementary-age children is 6-7 hours depending on the grade level and district, beginning at 7:30-8:30 AM and culminating at 2:00 to 3:00 PM. 
Elementary education is offered free of charge at American public schools, although parents may be required to purchase certain school supplies and books. Parents not comfortable with the public school setting can instead opt to send their children to one of the thousands of private schools across the country, albeit for an expensive annual fee. These schools, which are mainly operated by churches and private companies, can usually offer smaller classroom sizes and are bound by the same academic standards that govern the public schools
Elementary schools in the United States provide instruction in the fundamental skills of reading, writing and mathematics, with each grade building on the year before. Students are also introduced to several other subjects throughout this six-year stage of education, including history and geography (taught together as social studies), crafts, music, science, art and physical education. Foreign languages, which formerly were taught solely at high schools, are now being introduced during the last few years of elementary school in some areas, although in the majority of cities, schools still do not offer any foreign language instruction. All schools, however, now have specialized programs for those students whose first language is something other than English. These programs, which stress English learning as part of the curriculum, prevent students from falling back on their studies due to barriers in language.
Instruction in elementary schools is guided by a national curriculum, set forth by the United States Secretary of Education, which prepares students for studies at the secondary school level. In addition to the regular curriculum, all U.S. elementary schools are also compelled to offer Special Education programs. These programs are designed for students with learning delays and other disabilities that affect their ability to learn at the same pace as other students. In addition, many elementary schools offer Gifted Education programs. These programs are designed to address the needs of students for whom the regular curriculum in one or more subjects is not challenging enough.
In elementary school, the instruction is led by one teacher and the classroom sizes range from 20-30 students. Regular elementary school teachers must, at minimum, possess a four-year Bachelor degree and a one-year, “multiple-subject” teaching credential. Special Education classrooms are generally led by a teacher and a teacher’s aide. The optimal class size for these programs is 15 or fewer students, with a maximum of 20 students. Special education teachers must have a Bachelor’s degree and a Special Education credential from an accredited university.