The purpose of the project was to explore how a learning study (LS) based on variation theory could support the development of playful physics learning in early childhood education. The study explored what patterns of variation used during a three-cycle LS challenged and developed children's ways of discerning why a shadow occurred. The empirical material comprised a screening (n = 7), three video-documented interventions, and 78 individual pre-and post-test interviews (n = 39) at 4 -5 years old. Three somewhat different patterns of variation were implemented within a playful frame in the three groups. The results indicate low and non/significant improvements in cycle A, somewhat higher and significant improvements in cycle B, and substantially higher and significant improvements in cycle C. The study indicates a promising ability to combine a playful approach with the variation theory perspective to stimulate children's understanding of a quite advanced scientific phenomenon. The careful process of identifying potential critical aspects, the awareness of the relationship between the whole and its parts, and the concretization of simultaneity are discussed as key aspects of these findings.