This paper describes a 12-week cluster randomized controlled trial that examined the efficacy of BookNook, a virtual tutoring platform focused on reading. Cohorts of first- through fourth-grade students attending six Rocketship public charter schools in Northern California were randomly assigned within grades to receive BookNook. Intent-to-Treat…

Background: Efficacy trials in education often possess a motivating theory of change: how and why should the desired improvement in outcomes occur as a consequence of the intervention? In scenarios with repeated measurements, certain subgroups may be more or less likely to manifest a treatment effect; the theory of change (TOC) provides guidance…

Analyses were conducted with second graders, drawn from an ongoing multi-cohort randomized controlled trial (RCT), who had been identified for RCT entry based on comorbid reading comprehension and word-problem solving difficulty. To estimate pandemic learning loss, we contrasted fall performance for 3 cohorts: fall of 2019 (pre-pandemic; n = 47),…

Purpose: Key considerations in designing multilevel experimental studies are to efficiently use resources and to determine the sample size allocation such that designs have adequate statistical power. The utility of optimal sampling and power analysis results depends on accurate information about design parameters, such as intraclass correlations…