Research suggests that the incidents of self-harm among young people are increasing and age of onset of self-harm is decreasing. There is limited understanding of how widespread the problem of self-harm among younger school students is, and how schools respond to these incidents. This study used an in-depth qualitative approach to understand self-harm in children under 13, and how elementary schools respond including typical actions, support for the child and parental involvement. School psychologists in New South Wales, Australia (n = 17; 78% females), completed in-depth interviews detailing types of self-harm, prevalence and frequency, and how these incidents were managed, including student intervention approaches and participation of parents. Thematic analysis of interviews was conducted. Psychologists estimated the prevalence of self-harm in their schools was 6.5% and was increasing, with an average age of onset of 10.8 years. Self-harm was most often understood as a coping mechanism associated with anxiety, stress and being bullied. Six themes emerged from the interviews. School psychologists reported that self-harm occurs less frequently in primary school children than high school children, but noted these behaviours still require early intervention. Participants felt they were limited in the support they can provide students who self-harm, and wanted more training for all school staff and parents in identifying and responding to student self-harm. School psychologists are important in identification and management of self-harm, and they report they need further support in helping children who are engaging in self-harm behaviours. Upskilling teachers and parents may assist in reducing rates of self-harm among children.