Often used in research literature and technical reporting, the term cohort refers to a group of individuals who have something in common. In education, cohort is typically applied to students who are educated at the same period of time—a grade level or class of students (for example, the graduating class of 2004) would be the most common example of a student cohort. Cohorts may also be divided into demographic or statistical categories, or subgroups, by age, race, gender, socioeconomic status, or English-language proficiency, among other categories. Educators often track academic data related to specific student groups, such as standardized-test scores or graduation rates, and the performance of these cohorts is often compared to other cohorts.

While the use of the term cohort may seem like unnecessary jargon in some cases, it can be useful when cohorts overlap with or diverge from traditional grouping terms. For example, since class refers both to students at a certain grade level and to students enrolled in a specific course, the use of both senses of class could cause confusion in some contexts—cohort, therefore, becomes a useful synonym. Another example would be educational situations in which students begin an academic program at the same time, but then complete it at different times. In these cases, students might be considered members of the same cohort, but they may not proceed through an academic program at the same pace or earn in degree in the same year. For example, schools, districts, and government agencies often track four-year, five-year, and six-year graduation rates for a cohort of students who began school at the same time.