It is very difficult to increase students' interest and curiosity towards science only within the curriculum in the school. At this point, extracurricular activities help students link the knowledge they obtained in school with real life and get answers the questions such as "where will I use this information" or "why am I learning this information?" They enable students to see the abstract concepts they learned in the lessons concretely and to participate in the practices while increasing their interest and developing a positive attitude towards learning (1,2). The word 'extra' in Extracurricular is defined as, more than normal, expected, and needed. By this definition, it is understood that extracurricular include activities except for the school curriculum. For this reason, many different definitions of extracurricular have emerged, and extracurricular activities are divided into different categories (3).
Extracurricular activities are activities that are not included in the formal curriculum and students do not take notes. It may include sports, clubs, drama, broadcasts, outings, and other social activities. Although not included in the formal curriculum, it helps students have real-world experiences. In this way, students can experience the knowledge they learned in the classroom in real life by attending increases students' curiosity about mathematics extracurricular activities (4). While some extracurricular activities focus on increasing success and closing knowledge gaps outside of school hours, others focus on different purposes. Extracurricular activities aim to develop students' various skills such as creativity, art and culture, volunteering, and community participation (5). Extracurricular activities support learning and provide a comprehensive and balanced distribution of the curriculum by linking it to real life (6). Studies show that there is a positive relationship between extracurricular activities and transferable skills such as interpersonal skills, team-working skills, presentation skills, self-direction, and project management skills (7).
For many students, being a part of activities outside of the classroom is a lot of fun. Beyond this entertainment, physical activities, clubs, and other extracurricular activities have many benefits such as personal, social, and intellectual development. They also contribute to advancing students' academic and professional goals. Students' primary reason to attend these activities is personal interests and to share these interests with the other students. This opportunity gives chance to develop students' social skills. The students that experience co-operating with others for the first time by attending the clubs and the organizations also have a chance to develop their leadership skills. Studies show that self-motivation helps increase students' success. Being successful in activities that interest them enables students to manage their time well, and these habits are reflected in their schoolwork. There are many academic clubs related to academic subjects in high school and college. These clubs support classroom learning and promote the students' interests in the subject. Club members can plan to form study groups, invite experts, and arrange a trip. For instance, in a language club, students can watch foreign films, and eat foods that belong to other cultures. So it provides students to have cultural experiences. In this way learning a language can be enjoyable and more meaningful. In high school and college, athletics are very popular extracurricular activities. Team sports develop students' friendships and help them cooperate. On the other hand, students are aware of the importance of an active lifestyle and its benefits. As another extracurricular activity, debate clubs require a wide range of skills such as strong research skills, thinking quickly, and communicating well. In debate competitions, there is an established topic and rules. Participants should present the arguments they researched based on this topic and they should be able to think critically. So they provide students to improve analytical and logical reasoning skills and the ability to speak confidently. Performing art organizations such as music (band, orchestra, chorus) and drama clubs are very common in high schools and colleges. Participating in these clubs requires a lot of time for students. Most of them participate in group competitions between schools besides playing for their benefit. These organizations such as musicals and theater can compete internationally. They receive feedback from judges and have an opportunity to work with peers from other organizations. (8).
Extracurricular activities are not just activities such as excursions to pass time. It should be done within a plan and program, with the teacher's preparations. The teacher must be prepared for the questions of the students during the activity. The teacher should ensure the safety of the students and the efficient realization of the activity during the process. For this, it is necessary to correctly select and create learning environments that promote learning by doing. Even though extracurricular activities are not part of the formal curriculum, they help to increase research and inquiry, interest and curiosity, learning by doing, and the desire to learn, in line with educational and teaching purposes. Besides using the classrooms and laboratories offered at schools, using the out-of-school fields develops students' cognitive, affective and psychomotor behaviors (2).
OECD (2016) self-efficacy perceptions of students in extracurricular science activities affect their attitudes towards science learning positively. Students who actively participate in extracurricular science activities have a higher belief in fulfilling science-related tasks with pleasure (9). Students participating in extracurricular activities have positive perceptions of social-emotional security, adult support, student support, and school engagement (10).
In the study conducted by OECD in 2018, it was seen that the students of schools that offer creative extracurricular activities have higher reading scores. In addition, it has been observed that students who do mathematics as an extracurricular activity have more interest than those who do not. Low-performing students don't do this much because they think they will not get rewarded for their work even though they have to spend more time working. Because too much training does not lead to success. At this point, Extracurricular activities increase students' interest in mathematics by providing a quality, creative and interesting educational environment. Students who develop a positive attitude toward learning mathematics can motivate to study. Providing this training to students at an early age will increase their self-confidence and develop their skills (5).