As a result of clumsiness, carelessness and inexperience, fractures of the upper arm in children are very common. By the age of 7, these fractures are the most common of all fractures. The aim of this paper is to analyze causes of fractures, places where they occur and activities that contribute to increasing the risk of fractures of the humerus. The paper analyzed 243 children, treated at the University Hospital Center in Zagreb for fractures of the upper arm in the period from 2015 to 2019. Most injuries occured between the age of 5 and 9 with a peak incidence at the age of 7. Boys were injured more often than girls. Left arm was broken more frequently than right with distal third being the most often broken part of humerus. In most cases, it was an unstable fracture and it requiered surgical treatment. The main places where the fractures occurred were sports and athletic fields, somewhat less frequently at home, at school and on the street. Significant places of fracture are children's playgrounds where swings and slides stand out as the biggest risk contributors. Football stands out as the sport with the most fractures of the upper arm bone. Although most fractures in children heal without loss of function, fractures in children lead to other types of problems. The stress of hospitalization and surgical treatment, being absent from school and reduced activity for weeks or even months are just some of them. Hospital treatment and subsequent check-ups generate, also, a certain cost for the hospital. Considering the high frequency of fractures due to falls from swings, slides, trampolines and other devices in parks and children's playgrounds, when building new or upgrading older playgrounds, greater importance should be given to the issue of safety and mitigation of possible falls in order to prevent fractures and other serious injuries.