The aim of this final paper is to present the role of biological properties and the environment in the development of a child's competencies in kindergarten. By observing and analyzing the child, his characteristics and his actions in kindergarten activities, the educator gains insight into his personality, potentials, identity development, interaction with others, and respecting them, creates the conditions for the development of eight key competencies. In doing so, it respects and achieves the goals, principles and values of the National Curriculum of Early and Preschool Education. A comprehensive view of the child, respecting his rights, the need for responsible behavior and his overall development identified the basic assumptions that need to be met in order to create conditions for optimal development of the child in which the educator has a primary role. An analysis of the educator's role in the child's development shows that kindergarten is a place of joint learning and living in which the child is much more than a passive "recipient" of information at an early or preschool age, and the educator is much more than an authority that introduces discipline and rules and transmits knowledge on the child. The child has the role of a subject of upbringing and education who independently makes decisions, creates and participates in activities with others, contributes to the community, has an insight into his progress and works on his own improvement. On the other hand, the educator contributes significantly to continuous observation and analysis, documenting the child's behaviors and achievements and, most importantly, contributing to personal progress and professional development by committing to lifelong learning. The educator must be aware of the changes that accompany the child and his development and adapt and change practices for the purpose of the child's progress, and this requires constant personal growth and changing oneself and one's own principles to provide the child with quality education.