The purpose of this replication study was to examine the impact of the Teacher Study Group (TSG) professional development in vocabulary on first-grade teachers' knowledge of vocabulary instruction and observed teaching practice, and on students' vocabulary knowledge. Sixty-two schools from 16 districts in four states were randomly assigned to…

Contemporary state math standards emphasize that students must demonstrate an understanding of the mathematical ideas underlying the computations that have typically been the core of the elementary school math curriculum. The standards have put an increased emphasis on the study of fractions in upper elementary grades, which are the years during…

Multitiered systems of reading instruction and intervention, including response to intervention, are widely used in early reading by schools to provide more intense services to students who need them. Research using randomized controlled trials has compared innovative Tier 2 interventions to business-as-usual Tier 2 approaches and established a…

The extent to which teachers implement evidence-based practices, such as explicit instruction, is critical for improving students' mathematics achievement. The purpose of this study was to examine the effect of the kindergarten "Early Learning in Mathematics" (ELM) curriculum on teachers' use of explicit mathematics instruction in core…

This article examines the efficacy of a multitiered systemic reading intervention for increasing the intensity and quality of explicit literacy instruction that teachers provide in first-grade classrooms. Schools ("j" = 16) were randomly assigned to the treatment or comparison condition. In both conditions, teachers ("i" = 42)…

This article presents findings of an efficacy trial examining the effect of a multitiered instruction and intervention model on first grade at-risk students' reading outcomes. Schools (N = 16) were randomly assigned to the treatment or control condition. In the fall of Grade 1, students were assigned to an instructional tier on the basis of…