As underlined by the recommendations of the Kazan Action Plan (Unesco, 2017), motivating youth to adopt an active and healthy lifestyle became one of the priorities of the physical education (PE) course. Based on the motivational power of playful situations and the imaginary of the pre-adolescents, an Erasmus+ project called ObLoMoV (Obesity and Low Motility Victims) has been developed by seven partners coming from Italia, Belgium, Finland, Greece, and Slovenia (see https://www.oblomovproject.eu/ for all details). In its Belgian adaptation, activities focused on health messages have been integrated to the content taught (Franck et al., 2018). Accordingly, the aim of this paper was to determine how the pupils’ knowledge and practices were impacted by these specific activities. Nine classes of 5th and 6th grades (pupils of 11-13 year-old) were recruited in five different schools around Liege (Belgium). Pupils took part in a 10 lessons PE unit. Seven health topics were proposed during the unit (nutrition, sleep, physical activity recommendations .). Data were collected before (questionnaire at T0), during (informal pupils behavior, good practices) and after (questionnaire at T1) the implementation of the unit. The total amount of subjects comprised 176 pupils (95 boys). They reported more than 400 good practices implemented outside of school while 160 pre-post questionnaires have been collected and analyzed. At baseline, results seem to be mainly influenced by the grade (p=.057). After the unit, pupils’ knowledge seems to improve in several classes underlining overall positive short-term effects of the approach proposed. Further analyses will provide additional information about the impact of the independent variables. Provisional implication is that encouraging pupils to report regularly how they use what they learn during the PE course could contribute to increase the accountability of the subject. ; ObLoMoV: Obesity and Low Motility Victims – “physical short shocks” and “theatre short stories” to convert ...