The research aim was to examine some factors of physical activity in families with 5-6 years-old children and physical education in the kindergarten, and to assess the effectiveness of the created educational project of physical activity stimulation in a family. The following research methods were applied: the project of physical activity stimulation in a family, survey, group conversations with children, descriptive statistics. The project lasted for three months. 278 families with 5-6 years-old children from 17 Klaipėda preschool institutions participated in it. Children participated in physical education classes in the kindergarten twice a week. They learnt different tasks and games during them. The teacher continuously emphasised which tasks and games should be performed at home together with parents. Three pieces of homework were given every week (for 30 min). The homework consisted only of those physical activities, tasks, and games which were performed in physical education classes in the kindergarten; therefore, they were measured, uncomplicated, and realised in such a way that at least one of the parents could definitely perform them together with their child. The research data suggests that the majority of the 5-6 years-olds’ parents, participating in the project of physical activity stimulation in a family, had higher education, a half of them did mental, sitting job, and only a tenth did sport systematically. Parents thought that the majority of their children were physically active, often asked their family members to do sport together, a third of them attended sports and dance clubs. The majority of the parents were positive about children’s physical education in the kindergarten; however, more than four fifths did not assist in organising health and sport events. The majority of the children liked physical education classes during the project of physical activity stimulation in a family, and they willingly told their family members about physical activity content. Family members mostly performed homework tasks together with the child 1-3 times a week, but not systematically. Mother or father mostly did sport together with the child. A child, who is systematically physically trained in a preschool institution, can stimulate his family’s physical activity. Five-six year-old children liked being the organisers of physical activity in their family. During the project the children often asked their family members to perform together the tasks or games, they had learnt in the kindergarten, at home. They were able to reveal clearly to the teacher the situations of physical activity in their family. On the other hand, children are just a go between a teacher and their parents. They are unable to realise all their physical potential by themselves, defeat parents’ unwillingness to do sport together, therefore, close collaboration between teachers and parents is essential. Both preschool teachers and parents should see physical activity as a basic (self)-educational component, model child’s physical activity, create favourable physical and social environment.