Background: Stroke is a worldwide leading cause of disability, and around 50 million people are affected by stroke annually. Public stroke educational and awareness programmes can make a great deal of difference. Young children are in key position to seek urgent medical care if grandparents suffer a stroke, as grandparents are often their secondary caretakers. Objective: The objective of the current study was to design an educational intervention targeting children and, in parallel, directly involve extended family members. Design: Participatory action research. Setting: School-based education stroke intervention in Thessaloniki, Northern Greece. Methods: Over the course of 5 weeks, this intervention sought to educate 66 preschool children and their families through a series of novel activities that revolved around 4 superheroes, the FAST mnemonic and a medical emergency number. One superhero and their unique superpower was introduced every week through a PowerPoint presentation, a short animation video and a wide range of in-class and take-home activities, such as 'phantom speech', role-playing, funny face mimicking games, and rhyming poems. Children were also encouraged to identify their own family superhero so as to transfer their learning to real life. Results: Follow-up individual and group assessment pointed to encouraging results. Results from odd-one-out-tasks revealed that children were able to recognise the stroke symptoms in question. However, they performed more poorly on more complex tasks involving recall. Conclusions: Preschool children acquired knowledge of stroke symptoms which appears more solid when recognition is assessed. Assessment tasks involving substantial recall of information do not necessarily reflect the ability to detect stroke symptoms.