Impact of a Tier 2 Fractions Intervention on 5th Grade At-Risk Students’ Fractions Achievement

The goal of this efficacy study was to conduct a rigorous randomized controlled trial to evaluate the effectiveness of a small-group intervention in fractions for fifth graders who are performing well below grade level in mathematics. The impact of the fractions intervention was assessed on a range of measures: (a) Test for Understanding of Fractions-4th grade, Test for Understanding of Fractions-5th grade, Number Line Estimation 0–1, Number Line Estimation 0–2, Fractions Procedures, and Curriculum-aligned measure. In addition, to better understand the learning environment that lead to enhanced outcomes for this group of students, the CLASS observational system (Pianta, Hamre, & Mintz, 2012a) was used to measure the nature of the instruction in the intervention condition. In this rigorous large-scale RCT, a sample of 1,123 students from three school districts across two U.S. states were screened at the beginning of the school year using a fractions measure developed by the research team. Two hundred and five students who scored between the 15th to 37th percentile on the screening measure and received parental consent to participate were randomly assigned to the intervention (n = 102) and comparison (n = 103) conditions. Results from the final analytic sample of 186 students (87 in intervention, 99 in comparison) showed that students who received the fractions intervention performed significantly better on all outcome measures than students who did not receive the intervention. Effect sizes (Hedges’ g) ranged from .66 to 1.08 in absolute value, and p-values were all less than .0001 even after the Benjamini-Hochberg correction.