Will participation in a Dual-Immersion program increase students English language literacy compared to their mainstream classroom peers? Literacy scores on the DIBELS and WIDA Access were assessed over two years for 144 students to see if English Language Learners (ELL) are having more success in English literacy acquisition than their mainstream classroom ELL peers and English natives in the Dual-Immersion program compared to their mainstream classroom peers. During the two years students in the Dual-Immersion program were taught half of their day in Spanish and half in English. Their mainstream classroom peers were taught completely in English. For the class of 2021 there is no pretreatment difference for any groups except for Dual ELL compared to Dual English natives, for PSF p = 0.020 and WUF p = 0.000. For the class of 2022 there was no pretreatment difference between any groups except for Dual ELL compared to Dual English natives, Dual ELL students were behind their native English speaking peers on every assessment on the DIBELS. For both the class of 2021 and 2022 there were no consistent significant differences between classes except for Dual ELL compared to Dual English natives. For the class of 2021 on post treatment assessment there was still significant difference in PSF p = 0.027 and WUF p = 0.002. For the class of 2022 pretreatment assessment showed significant difference on every assessment piece of DIBELS; in post treatment assessment there was still significant difference in ISF p = 0.004, LNF p=0.026, PSF p = 0.044, WUF p = 0.001 and ORF p = 0.024. Based on the results the Dual Immersion program is showing successful because there are not significant differences across grade levels. It is however, not decreasing the gap between ELL and English natives within the Dual Immersion program.