@hashimoton2020 American elementary schools have 6 years, but the first year is kindergarten so it doesn't have a number. The last year of elementary school is called "5th grade". The last year in middle school is called "8th grade". High school lasts 4 years and the last year is called "12th grade".
I see. Actually my son had enrolled into an elementary school after a kindergarten. My family left California before he graduates, so I’m not sure whether the elementary school consists of 5 years or 6 years.