These days, children spend a lot of time sitting, starting from the school where they sit 4 hours per day from age of 7, which increases to 7 hours per day to the age of 18. It is scientific proved that human organisam mostly changes from birth to the adolescent age, both intelectual and physical way, so it is very important to direct the child to it's proper and healthy development. Todays sedentary lifestyle is characterized with lack of physical activity, prevalence of the obesity amoung the children and adults, and bad posture, which leads to big health problems, causing future financial problems and lowering the quality of life. The sitting posture of school children during lessons, by computer desks and watching at the mobile phones, tablets and TV, affects spine very bad which may in future escalate in bigger spine problems. It is recommended that the school bag weight 10% of the full body of the school child, but in reality the weights of the school bags go up to 20%. Some children at the beginning of the school age have postural problems (scoliosis, flat feet and etc.) and when you add the excessive weight of the school bags the problem gets even bigger. The amount of books between a schoolchild going to 1st grade and the one going to 5th grade is almost similar and the difference between their stage of development is big. Chronogical and biological age of children is very individual and the weight they carry is the same. One of the problem is the infrastructure of the schools, the lack of room for leaving the books and the equipment for physical education classes which forces the children to carry the books and equipment every day. It is very important to find a right solution to all of these problems but in the same time to preserve the quality of teaching. By the right and well-timed diagnosis, with targeted choice of kinesitherapy exercises and by raising awareness of the importance of physical activity is possible to prevent most of the aforementioned problems.