A Citizen Science approach to building the evidence base is well established in many science disciplines, but is far from main stream in the social sciences. Prompted from the inquiry by the Australian Government's Productivity Commission into the National Education Evidence Base and taking Early Childhood Education (ECE) as an example, this paper aims to provoke discussions about the possible contributions of a Citizen Science approach to broadening the methodological repertoire in ECE research and to positioning ECE research more powerfully in the politics of evidence. It argues that ECE stakeholders' involvement in building the evidence base through a Citizen Science approach could have the potential to make significant contributions to knowledge construction in ECE.