A primary purpose of early childhood education and interventions is to promote children's acquisition of knowledge and skills linked to later social competence and academic success. In this report, special attention is given to summarizing what has been learned about early childhood classrooms as contexts for development and learning, the kinds of instructional practices and curricula that appear to be efficacious for enhancing children's development and learning, the ways in which children's skills and learning can be reliably and validly documented, and approaches for improving teachers' and other practitioners' (e.g., speech, occupational, or physical therapists) instruction, given hypothesized linkages between instructional quality, instructional effectiveness and children's learning. For this research synthesis peer-reviewed journal articles and chapters that were products of early childhood research projects funded by the Institute of Education Sciences (IES) from 2002 through 2008 were examined. These papers included both empirical studies as well as theoretical pieces. The task was to synthesize what has been learned thus far through IES early childhood research grant activities. This is not a typical synthesis intended to provide a grand overview of research in a field, nor is it a meta-analysis that quantitatively synthesizes a specific body of work. Rather, the task was to look across the range of projects that IES has funded to determine what has been learned and where progress has been made as a result of IES funding, and to provide suggestions for further research in early childhood education. (IES-Supported Research Projects and related Publications included in this Synthesis are appended.) (Contains 157 footnotes.)