The Glossary of Education Reform tells us that:

Co-curricular refers to activities, programs, and learning experiences that complement, in some way, what students are learning in school—i.e., experiences that are connected to or mirror the academic curriculum.

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Co-curricular activities are typically, but not always, defined by their separation from academic courses. For example, they are ungraded, they do not allow students to earn academic credit, they may take place outside of school or after regular school hours, and they may be operated by outside organizations. That said, these traditional distinctions between academic and co-curricular programs are being eroded in some schools—see learning pathways for a more detailed discussion.

A few examples of common educational opportunities that may be considered co-curricular include student newspapers, musical performances, art shows, mock trials, debate competitions, and mathematics, robotics, and engineering teams and contests. But given the differing interpretations of the term, as well as its many potential applications, it’s best to determine precisely how co-curricular is being used in a particular educational context.

Co-curricular vs. Extracurricular

Generally speaking, co-curricular activities are an extension of the formal learning experiences in a course or academic program, while extracurricular activities may be offered or coordinated by a school, but may not be explicitly connected to academic learning. This distinction is extremely fuzzy in practice, however, and the terms are often used interchangeably. Athletics, for example, are typically considered to be extracurricular activities, while a science fair would more likely be considered a co-curricular activity, given that students are learning science, participation may be required by the school, students may be graded on their entries, or a science teacher may coordinate the fair. Still, in some schools certain athletics activities might be considered “co-curricular,” while in other schools a science fair may be labeled “extracurricular.”