Questions of how best to support both children’s emotional well-being and behaviour in schools are pervasive. The efficacy of an intervention planning tool to support internalising and externalising emotional needs and promote early intervention was explored in a small-scale case study. Adults were trained in two primary schools to carry out the intervention planning tool which they did with a total of 12 children. The intervention planning tool was based on principles of multi-element plans (MEPS) and target-monitoring and evaluation (TME). Data from scaling (TME), the Strengths and Difficulties Questionnaire, a questionnaire based on the School Children’s Happiness Inventory (SCHI), and interviews with school staff and children were analysed using statistical and thematic analyses. Findings indicated that the intervention planning tool supported positive outcomes overall for the children, and that while some barriers were identified, several unexpected advantages were also revealed.