Even though middle schools and junior high schools both strive to prepare students for high school, each has its own specific purposes and functions. Middle schools are more student-focused, and junior highs are more subject-oriented. Students at junior high schools typically attend six to eight different subject-specific classes per day, while most middle school students have block classes that last two or more hours each and cover a blended mix of subjects.

Grade Levels

Junior high schools are for students in grades seven through nine, and middle schools are for students in grades six through eight. As a result, middle school students start high school in ninth grade, and junior high students start high school in 10th grade. In the mid-1900s, educators and administrators believed junior high schools helped prepare adolescents for high school without putting them in the same building with older teenagers, according to Kelly Bedard and Chau Do's research at the University of California in Santa Barbara. In the late 1960s, middle school supporters argued that sixth-grade students benefitted from being separated from elementary school children because it sped up their academic progress. According to the Department of Education's National Center for Education Statistics, the number of middle schools rose 462 percent from 1970 to 2000 -- 11,700 middle schools in 2000 versus 2,100 in 1970. During the same period, the number of junior high schools declined by 57 percent from 7,800 to 3,300.

Educational Focus

Junior high schools and middle schools have different educational focuses. Middle schools are more student-oriented, and junior high schools are more subject-centered. For example, teachers at junior highs teach a specific subject, such as math, science or English, all day. Students rotate to different teachers for each subject. Classes are structured and offer little flexibility, lasting approximately one hour each. Middle schools focus on the combined developmental and educational needs of students, rather than academic subject matter alone, according to the Association for Middle Level Education (AMLE). For example, a teacher might combine English, social studies and writing lessons into one unified session.

Classroom and Content Organization

Students at junior high schools typically have six to eight classes per day, including a free period, known as a study hall, to work on assignments independently. Classrooms are organized by subject and grade level. Middle-school students have block scheduling that coincides with collaborative lesson plan goals created by middle school teachers, according to the AMLE. For example, middle-school students might have a block period that lasts anywhere from 45 minutes to 2 ½ hours. Students from different grades might also intermix to work on projects. Middle-school students don't have every subject every day and often have extra time to explore elective classes, such as art, theater, music and physical education.

Desired Outcomes

Teachers often work together in middle schools to meet state curriculum requirements. They have combined planning sessions to develop unified, all-encompassing lessons. The goal of middle schools is to give sixth-, seventh- and eighth-graders opportunities to work in a collaborative environment that's more socially and academically challenging than elementary school. On the other hand, junior high schools are designed to be miniature high schools, training students to keep up with the books, assignments and requirements of individual classes and teachers, according to Brush, Colorado middle school principal, Sherry Kyle, on the Brush News Tribune website. It's far less likely to see common planning sessions at junior high schools.