Historically, schools in the US have borrowed the European system of school organization, a system that separates students into grades by chronological age. In general, children begin formal schooling at the age of six in what is referred to as the first

Historically, schools in the US have borrowed the European system of school organization, a system that separates students into grades by chronological age. In general, children begin formal schooling at the age of six in what is referred to as the first grade. For the most part, students progress through twelve grades; however, some students who do not meet minimum requirements for a particular grade may be asked to repeat the year.
Graded schools are divided into primary grades, intermediate grades, and secondary grades. Primary education includes grades 1 through 5 or 6, and may also provide kindergarten as a preparation for first grade. Referred to as elementary school, these grades are usually taught by one teacher in a self-contained classroom. Intermediate grades begin with grade 6 or 7 and offer three years of instruction. At this level, teams of teachers may collaborate to provide subject-based classes similar to those offered in high school. Viewed as a preparation for high school, intermediate education is known as junior high school. At grade 9 or 10, secondary school begins. Classes taught by subject specialists usually last about fifty minutes to allow a student ten minutes to move to the next class before it begins at the top of the hour. At the end of twelve successful grades of instruction, students are eligible for a secondary school diploma, more commonly called a high school diploma.
Summarize the main points in the lecture, explain how they cast doubt on the ideas in the reading passage.