Supplementary activities help in the personal development of the students, and these activities can be considered as hobbies. For instance, if a student in a professional agricultural program learns about rearing of sheep or harvesting of herbs, then it will be a supplementary activity. Co-curricular activities help a student to sharpen the existing academic knowledge when he participates in debates, group discussions, sports, quizzes, etc. Hence, co-curricular activities enable the student to achieve professional development.
Supplementary activities are optional, and not all students may be inclined to participate in the same supplementary activity. For instance, sharpening the blade of a lawnmower may be an optional activity for students enrolled in an agricultural program. On the other hand, a school may require its students to participate in co-curricular activities like music classes and debate. Some schools may make it mandatory for students to participate in a co-curricular activity, such as intercultural service.
Supplementary activities are taken by the interested students who want to pursue these activities as hobbies. Since these are taken solely by a limited number of students for the sake of personal satisfaction and passion, no formal credit or grading is awarded. However, in the case of co-curricular activities, credits may be given since these activities are related to the formal learning process and professional development of the students.