The interprofessional, interagency model PLUSS offers education for preschool teachers on how to detect and support preschool children with neurodevelopmental symptoms. A total of 119 preschool teachers used the Strengths and Difficulties Questionnaire (SDQ) to assess behavioural problems and the Children's Engagement Questionnaire (CEQ) to evaluate engagement and social interaction in 119 preschool children, before and after their PLUSS education. After education, the preschool teachers rated fewer behavioural problems (total SDQ p < 0.001) and increased engagement and social interactions (CEQ p < 0.001). In conclusion, the PLUSS preschool teachers' education and screening with the SDQ and the CEQ facilitate assessment of behavioural problems, engagement and social interaction in preschool children. Increased understanding of neurodevelopmental symptoms seems to influence how preschool teachers manage a child's behaviour, which indirectly changes the child's engagement and social interactions for the better. The preschool teachers expressed perceived needs, especially to learn how to deal with a child's emotions and behavioural regulation, and their interactions with other children.