Children experience physical phenomena and formulate an epistemological worldview before contact with school science. School science extends thought about the same phenomena to deeper levels but does not always link with out-of-school experiences. This study explored preservice teachers' indigenous knowledge or tacit knowledge about the playground swing and its use to teach the physics of the simple pendulum. The preservice teachers' indigenous knowledge experiences with playground swings may be a pivot for linking their physics teaching to out-of-school experiences. A phenomenological research design was used to explore experiences of eight preservice teachers. Data were collected using focus group interviews and personal interviews and were thematically analysed. Findings show that young players become aware of relationships between variables; they are attracted to the swings for specific reasons; they connect experiences at swings with physical laws. However, pre-service teachers are not able to connect this tacit knowledge with formal science. Yet teachers should realise that school physics explains everyday experiences which they know in their vernacular. The lack of such a link may disadvantage learners in understanding ideas expressed in English, which is not their mother tongue. Thus, teachers need to link indigenous tacit knowledge with school physics in order to develop effective teaching strategies.