National Research
Thomas and Collier’s longitudinal study conducted across 35 school districts in 16 states compared results on state and national tests from students in different instructional models. The study has been replicated several times, always confirming the findings. Thomas and Collier found that Spanish-speaking students need six years of bilingual instruction, with eight years preferable for full gap closure. For our students, that means that bilingual instruction in grades K-5 is extremely important. While it is preferable that students receive Spanish instruction beyond fifth grade, we see a strong positive impact for student achievement with just 6 years of bilingual instruction.
DPS Research
DPS research confirms Thomas and Collier’s finding that students who receive bilingual instruction acquire English more quickly than their peers who do not. We have also found that students enrolled in bilingual programming are significantly more likely to be on-track to becoming fully English proficient within 6 years and that students enrolled in bilingual programming consistently outperform their peers on Spanish assessments.
