Description: Analysis of the scientific literature let us establish the following: 1. The problem of school transition is acute in many countries, where the phenomenon of school transition exists. 2. Various aspects of the phenomenon of school transition has been scrutinized by scientists of many countries, such as, the USA, Germany, Sweden, Japan, Holland, etc.. 3. Assessments of marked school transitions are quite contradictory from a complete assent to the school transition as a rite guaranteeing an opportunity for children's social and psychological maturation as well as a phenomenon guaranteeing the quality of education, to an absolute rejection due to the mischief done to the child's personality as well as due to deepening of segregation and inequality in the society and occurrence of social exclusion groups. 4. In spite of ambiguous results of some research it is commonly accepted that school transition is a risk factor, which can harm pupils' academic, psychological and social functioning. 5. The school transition has different impact on pupils. Some of them function better at new schools, the others' functioning remains the same as is was at their old schools, the third start functioning worse. Hence, there is an educational problem: how to help pupils to pass from one school to the other successfully, trying to prevent decrease in their functioning at the new school. 6. Scientists admit that there are some factors which can help pupils to overcome this risk and function successfully adjusting themselves to the new school. These factors lie in different levels, such as, family, school and the whole educational system. However, we must admit that so far we lack a clear scientifically grounded system to control these factors. Two years ago the researches on school transition were also started in Lithuania. They were initiated by the Ministry of education and science of the country. In 2004 and 2005 by request of the Ministry of education and science were conducted researches aiming to reveal a variety of problems, related to the school transition. In this report is presented a part of the research conducted in 2005. In this part we aimed to answer a problem question as follows: Is there a relationship between pupils' participation in leaving/initiation programs carried out at schools and the pupils' academic, psychological and social functioning at the new school? Methodology: The main method, used to achieve the goal of this research, was a survey by questionnaires. By means of stochastic systemic sampling we formed a sample of 345 schools of the country, and there stochastically sampled 920 pupils, who changed schools in 2004. All the survey participants were pupils of the 5th to 10th forms from basic, secondary schools and gymnasiums. In Lithuania children start going to school at the age of 7, therefore the average age of pupils of the 5th form is 11 years old, and the average age of pupils of the 10th form is 16 years old. The main types of schools in our country are basic schools, which pupils attend from the 1st to 10th form, secondary schools (with the form range from the 1st to 12th) and gymnasiums, where pupils study four years, corresponding to the 8th to 12th forms of the secondary school. The data gathered during the research were processed with SPSS program, using various procedures for statistical analysis. Conclusions: Pupils' successful functioning at school is strongly related to the leaving/initiation programs carried out at schools. In most cases academic, psychological and social functioning of newcomers is better in cases where the old school prepares pupils for the transition to a new one; where the new school head teachers show their interest in adaptation of the newcomers and organize provision with appropriate information about their school; where during the first months form teachers give more attention to newcomers (informing, helping them, explaining and arranging their classmates' help); where subject teachers are kind and do not write poor marks during the first months; where classmates help, parents take care and the child him/herself tries to do his/her best to start participating in life of his/her new form and school.