The proposed study aims to improve our understanding of early math instruction and how to provide children with the best mathematical opportunities in these early and important years of school. The purpose of the study is two-fold. First, through classroom observations and coding of curricular materials, we will provide new and valuable information about the alignment of mathematics content and instruction across the early elementary grades (kindergarten through grade three). Second, we will explore two factors that may account for variation in mathematics instruction: context and curriculum. Through classroom observations, we will provide insight into the extent to which mathematics instruction in kindergarten varies across schools serving vastly different student populations. By coding three different widely used early mathematics curricula, we will explore the extent to which instruction is likely to vary depending on the curricular program that is in use.