The spine carries the head, supports the torso, surrounds and protects the spinal cord and is responsible for the overall movement of the body. Spinal deformity disrupts the harmony of these functions. Poor posture is the first sign of spinal deformity. In the population of school children, spinal deformities occur due to the modern way of life and lack of physical activity. It is important to emphasize the need for physical activity in children to strengthen the muscles of the back and the whole body. Certain targeted posture exercises can affect more proper muscle development and improve circulation. Exercises can be conducted in a physical education class. The most common spinal deformities include kyphosis, lordosis and scoliosis. Each of these deformities has a certain degree of progression, and depending on this degree, targeted therapy is given. The aim of this paper was to explain each of the spinal deformities, to suggest exercises that can alleviate each of the spinal deformities and to conduct a study to determine the percentage of younger school age students with spinal deformities attending primary school in Zaprešić, to determine whether there is a gender difference and to vertify whether there is an effect of body weight and height on the spinal deformity. The research, which was conducted on a sample of 52 elementary school students in Zaprešić, aged between 6 and 7, obtained a percentage of students with spinal deformities, amounting to 11.53%. Research has shown that there is not a difference in gender in the occurrence of spinal deformities. The results showed that there was no statistically significant correlation between body height and body weight with spinal deformity.