In current research on early bilingual education programs, it is argued that second language teaching has many contributions to the child. Especially Critical Period HypothesisStudies based on , indicate that bilingual education programs have positive contributions to the child's language and cognitive development. In these studies, it is generally emphasized that early childhood years are a critical period not only in the mother tongue but also in the second language, and it is stated that the processes of learning the mother tongue and the processes of learning the second language are similar. It is also noted that bilingual early childhood education programs are more successful than monolingual education programs in children's language education.
Krashenexplains that language development in children's brains begins at the age of two and this development continues until adolescence. If the child starts learning a foreign language during this period, he can learn the foreign language as easily as his mother tongue.
According to Lambert, if the child who begins to acquire his/her mother tongue begins to study a foreign language before passing the critical age period, he will be more successful in his future education than his peers. This predisposition towards foreign languages acquired in early childhood also contributes greatly to the cognitive development of children.
Linguists think that the problem-solving skills of children who learn a foreign language before school are also very strong.
According to Beydoğan, the child's perception of the outside world and interaction with it are closely related to the development of the cognitive process. The development of the cognitive process is based on interaction. The only factor that provides this interaction is language. Therefore, we should attach great importance to language development.
Anşin states that teaching a foreign language at an early age develops the child's quick intelligence and increases his ability to understand his mother tongue.
As Halliwell states, children are cognitively equipped to learn a foreign language in the preschool period. However, instead of teaching the language directly to children, a foreign language can be taught indirectly by using games, songs and nursery rhymes.
According to Biketençayev, the period when children's brain functions are most intense is the period between the ages of 0-5. The language the child learns at these stages is almost as good as his mother tongue. The child who learns a foreign language at an early age is psychologically more mature than his peers.
According to Kara, a child who is exposed to a foreign language at a young age can compare his own cultural values with the cultural values of foreign countries in the future and become a more tolerant, universal individual with strong communication skills. In other words, language education at an early age has positive effects on the child's social, individual and cultural development. .
Akdoğan states that the child's brain development occurs between the ages of 2-5 and completes this process at the age of 6. The linguistic awareness of the child is intense at this age. If foreign language teaching in a natural environment can be prepared in accordance with child psychology and development, children can learn languages much more easily at this age. A correctly structured language education can make positive contributions to the child's mental development.
Gündoğar argues that children who learn a second language in early childhood develop a linguistic awareness that different languages have different rules by comparing the similarities and differences of sounds, words and sentences between the two languages.
In his study, Bleyhl determined that children who received second language education began to use the second language without an accent at the end of the second year and were successful in using certain language structures independently. Based on this finding, the researcher emphasized that acquiring a second language at an early age and developing second language speaking skills in children contribute positively to self-expression.
Doyé states that second language education, which begins at an early age, not only affects the social and individual development of the child, but also contributes positively to its cultural development, especially the child will gain awareness of other languages and cultures other than his own language and culture. It also emphasizes that children will have a positive approach to people from different cultures by laying the foundation for the acquisition of intercultural communication skills.
According to Genç, children who encounter a different language at an early age will compare their own cultural values with the cultural values of foreign countries in the future and become more tolerant, universal individuals with strong communication skills.
To summarize the views on second language education in early childhood years, a child who acquires a language other than his/her mother tongue will develop his/her thinking skills by gaining sensitivity about which language he/she should use in which situation, and enabling him/her to decide when, with whom, in which situation, and in which language he/she should communicate. Especially in social communication, switching from one language to another and constantly changing the spoken language will create flexibility of thought, which will increase the child's ability to move and creativity.
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