This study examined whether the efficacy of ROOTS, a 50-lesson mathematics intervention program focused on whole number concepts for at-risk kindergarten students, differed by group size and whether initial skill moderated intervention effects by group size. The study utilized a randomized block design with at-risk students (n = 1,251) within…

This study examined whether the efficacy of a 50 lesson mathematics intervention program focused on whole number concepts for at-risk kindergarten students, ROOTS, differed by group size and whether initial skill moderated intervention effects by group size. The study utilized a randomized block design with at-risk students (n = 1,251) within…

A concerning number of students enter kindergarten facing an intractable variation of mathematics difficulties (MD). This study investigated the impact of an explicit, core kindergarten mathematics program on the mathematical outcomes of kindergartners who demonstrated risk for severe MD at kindergarten entry and examined whether these students…

A concerning number of students enter kindergarten facing an intractable variation of mathematics difficulties (MD). This study investigated the impact of an explicit, core kindergarten mathematics program on the mathematical outcomes of kindergartners who demonstrated severe MD at kindergarten entry and examined whether these students improved…

This study uses a regression discontinuity design to evaluate the impact of seventh-grade interventions delivered by 25 schools on the reading and school engagement outcomes of struggling readers. Students in participating schools were assigned to intervention (n = 1,495) or comparison (n = 4,397) conditions, based on their state reading…

We present the results of a study of local education agency (LEA)-based interventions to improve the reading outcomes of struggling readers in sixth grade. The sample included 1,076 intervention students and 3,644 comparison students. Regression discontinuity was used to evaluate intervention impact. The study contributes to the field by…

Group size and treatment intensity are understudied topics in mathematics intervention research. This study examined whether the treatment intensity and overall intervention effects of an empirically validated Tier 2 mathematics intervention varied between intervention groups with 2:1 and 5:1 student-teacher ratios. Student practice opportunities…

We report on a practitioner implementation of Fusion, a first-grade mathematics intervention. Studies such as this evaluation of a loose implementation under realistic conditions are important to curriculum developers' understanding of how evidence-based programs and tools work under a variety of implementation scenarios. In this…

We report on a practitioner implementation of Fusion, a first grade mathematics intervention. Studies such as this evaluation of a loose implementation under realistic conditions are important to curriculum developers' understanding of how evidence-based programs and tools work under a variety of implementation scenarios. In this…

This study used a randomized controlled trial design to investigate the ROOTS curriculum, a 50-lesson kindergarten mathematics intervention. Ten ROOTS-eligible students per classroom (n = 60) were randomly assigned to one of three conditions: a ROOTS five-student group, a ROOTS two-student group, and a no-treatment control group. Two primary…

A growing body of research suggests that the effects of core mathematics instruction on student mathematics outcomes may not be uniform across different skill levels in mathematics. This study investigated the extent to which observed components of explicit mathematics instruction explained why students' initial mathematics achievement was…

The purpose of the present article is to report on a large-scale investigation of six school districts' implementation of an initiative aimed at reducing dropout rates by improving reading achievement in the middle grades. Data for the Middle School Intervention Project (MSIP) were collected in 25 middle schools across the state of Oregon. We…

Accumulating research has established explicit mathematics instruction as an evidence-based teaching practice. This study utilized observation data from a multi-year efficacy trial to examine the longitudinal effects of a core kindergarten mathematics program on the use of explicit mathematics instruction among two distinct groups of teachers: one…

Accumulating research has established explicit mathematics instruction as an evidence-based teaching practice. This study utilized observation data from a multi-year efficacy trial to examine the longitudinal effect of a core kindergarten mathematics program on the use of explicit mathematics instruction among two distinct groups of teachers: one…

This study used a randomized controlled trial design to investigate the ROOTS curriculum, a 50-lesson kindergarten mathematics intervention. Ten ROOTS-eligible students per classroom (n = 60) were randomly assigned to one of three conditions: a ROOTS five-student group, a ROOTS two-student group, and a no-treatment control group. Two primary…