Abstract—During recent years, there are huge discussions regarding 21st century education; Experts, scientists, educational specialists offer different ideas, results, and conclusions about how to improve educational processes in schools and how to develop students' 21st century skills; one of the important steps that have been taken in this direction is to introduce programming (coding) from the first grade as an independent subject in schools. The goal of this paper is to find out why it is important to teach programming in school. The main questions about this issue are: what are the reasons to teach programming? What are the main problems in the teaching process? How to teach programming? Answers to these questions are not always connected with each other and the teachers, who really create education in the classroom, need much more precise and complete information to what to teach and how to teach. Because of these issues, we decided to research this field and share our own experience, which we believe is successful in our school: we teach programming through the project-based learning method. Using this method, it is possible to develop 21st century skills and teach the basics of computer science from elementary school. In this paper we will discuss about secondary school students; by the end of the project, the 10th grade students have solved one of the problems of the school community - they have created educational games on the topic of ecology; games were created by the request of elementary school teachers; this year the games are successfully used in learning process.
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