Most prekindergarten (preK) teachers are probably unfamiliar with the "College, Career, and Civic Life (C3) Framework for Social Studies State Standards." John McDonnell, who teaches a class of eleven four-year-old children, also had not heard of it until he attended the author's workshop on early childhood social studies practices, which included an introduction to the C3 Framework. At the workshop, teachers from preK through third grade learned about using the Four Dimensions of the C3 Framework's Inquiry Arc: (1) developing questions and planning inquiries; (2) applying disciplinary concepts and tools; (3) evaluating sources and using evidence; and (4) communicating conclusions and taking informed action. Even though the C3 Framework focuses on the K-12 curriculum and was not designed for preK teaching, Mr. McDonnell wondered if it could be used to organize inquiry-based social studies lessons for his prekindergarten students at the LSU Early Childhood Education Laboratory Preschool in Baton Rouge, Louisiana (ECELP). This article describes a collaboration between the author and Mr. McDonnell to create the landmarks unit, combining knowledge about young children and social studies to plan for each of the four Dimensions. This prekindergarten social studies inquiry, created through use of the C3 Framework, is probably one of the first of such studies. The experience suggests the C3 Framework can provide a useful, guiding structure for early childhood teachers to ground inquiry experiences in social studies disciplines.