The present study reports findings on pre-service teachers' thinking during planning and implementing play-based art activities. "Thinking" (in the present study) is informed by discourses emphasising art teaching and learning in relation to play and theoretical assumptions conceptualising planning as "practice of knowing." Pre-service teachers' thinking was explored through: (a) a tool "skeptikó" (a series of questions), created by the researchers to initiate inquiry during planning and provide evidence about participants' "practice of knowing," and (b) a semi-structured interview using the method of photo-elicitation. Classroom observation, researchers' reflective notes, document analysis ("skeptikó") and photographs were used in conjunction with data gathered from semi-structured interviews to confirm the findings. The findings suggest that there is a relationship between pre-service early childhood teachers' thinking (planning) and practice (implementation). The rationale behind their decisions appears to compete with their thinking on philosophical/moral choices (knowing why). The notion of space has been challenged through artistic practices incorporating "play," while art activities were characterised as playful, reinforcing active learning. The study highlights the significance of thinking through documentation, as this was found to contribute to reflective pedagogical practices.