First-grade mathematics curriculum has been typically constructed to emphasize the development of whole number and operations. Topics addressed to a lesser extent include algebraic thinking, measurement, and geometry. In this research study, we suggest an alternative to this balance of topics. We compared prior research and learning expectations from the Common Core State Standards for Mathematics (CCSSI, 2010) against a learning progression which we proposed as one that develops early algebraic thinking. We described lesson clusters and shared evidence of student thinking to illustrate our learning progression. Findings from this work have implications for what has been considered the start of the learning progression for mathematics.