¡Arriba la Lectura! Illinois K–5 Impact and Implementation Study

Cobblestone Applied Research & Evaluation, Inc. conducted a retrospective longitudinal study to examine student literacy outcomes and educator implementation experiences associated with HMH ¡Arriba la Lectura!™ during the 2024–2025 school year in one Illinois public school district. The study focused on English learner students in Dual Language classrooms and examined changes in reading performance from beginning of year (BOY) to end of year (EOY) in English and Spanish. Student outcomes were measured using two district‑administered assessments: NWEA^® MAP^® Growth™ Reading (Grades K–5) and the HMH Spanish Growth Measure® (Grades 2–5), providing complementary evidence of literacy growth in English and Spanish and progress toward grade‑level expectations.

Students in Dual Language classrooms implementing ¡Arriba la Lectura! demonstrated statistically significant growth in English and Spanish literacy from BOY to EOY. These parallel gains are consistent with research on literacy development in Dual Language settings, including studies documenting cross-linguistic transfer. However, transfer processes were not directly measured in this study. This pattern was reflected across both assessment measures, with Spanish literacy growth evident in increased scaled scores and meaningful shifts in grade-level performance distributions, including fewer students below and more students on or above grade level by EOY.

Educator survey and focus group findings provide instructional context for these outcomes, with teachers reporting consistent program use, coherent pacing, and growth in students’ Spanish literacy skills. Teachers identified instructional components such as Read-Alouds, structured routines, and opportunities for discussion as supporting engagement with academic Spanish and development of oral language alongside reading. While the single-group design does not permit causal attribution, the findings provide locally relevant evidence aligned with state and district priorities for high-quality Dual Language programming and, in combination with a well-defined logic model, support classification of this study as meeting ESSA Tier 4 (Demonstrates a Rationale).

When considered alongside the companion Into Reading study conducted in the district's monolingual English classrooms, the findings contribute to a broader picture of literacy development across instructional models.