Compulsory education in the US begins at the age of five, when a child enters kindergarten, but most children attend pre-school from the age of three or four. While kindergarten falls under the public education system, and is therefore free, pre-schools are run privately and parents will be expected to pay fees.

Naturally, the schooling system varies quite considerably from state to state in the US. Generally, in most school districts, the system is divided into three levels:

Elementary school – Kindergarten to Grade 5

Middle school – Grade 6 to Grade 8

High school – Grade 9 to Grade 12

In most states, it’s compulsory for children to attend school until at least the age of 16, but children will usually continue their education until they graduate. In other states, schooling is mandatory until the end of high school.

https://www.expatarrivals.com/americas/usa/education-and-schools-usa