Background: There is an increased focus on randomized trials for proximal behavioral outcomes in early childhood research. However, planning sample sizes for such designs requires extant information on the size of effect, variance decomposition, and effectiveness of covariates. Objectives: The purpose of this article is to employ a recent large…

Research Findings: In Study 1, we observed 32 Chinese kindergarteners playing a number board game with their caregivers in dyads. Number board game playing provided important opportunities for kindergarteners and their caregivers to talk about an array of number concepts, but their numeracy-related exchanges rarely went beyond counting. In Study…

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…

This meta-analysis summarizes research on the effects of a comprehensive, interactive web-based software (AXXX) on the development of reading competencies among kindergarteners and elementary students. Findings from seven randomized control trials and quasi-experimental studies undertaken in a variety of contexts across Canada, Australia and Kenya…