This article reports on a longitudinal, quasi-experimental comparison of two English language development (ELD) models implemented from kindergarten through Grade 3 to support oral English language development among Spanish-speaking English language learners (ELLs). Specifically, the study examined oral English language proficiency among students who received only integrated English language development (I-ELD; n = 39) and students who received I-ELD with 30 minutes of daily designated ELD (D-ELD) entailing four specific routines and strategies (n = 65). The study also compared oral proficiency with English-only speakers (EO) from the same school (n = 47). Oral language proficiency was measured by the IDEA Proficiency Test (IPT I-Oral; Ballard & Tighe, 2017). A repeated-measures analysis of variance (ANOVA) across Grades 2 and 3 indicated significant (p < 0.001; [eta][superscript 2] = 0.53) increases in oral proficiency for ELL students who received D-ELD. A follow-up analysis of covariance (ANCOVA) indicated significant positive effects (p < 0.001; [eta][superscript 2] = 0.19) of the D-ELD approach on ELL students' oral proficiency compared to only I-ELD in Grade 3. The ANCOVA also found no significant (p > 0.05) differences in oral proficiency between ELL students who received D-ELD and EO students in Grade 3, indicating similar oral English skills. The D-ELD model's instructional strategies and practical implications are discussed.