Federal law defines eligibility for English learner (EL) classification differently for Indigenous students compared with non-Indigenous students. To be EL-eligible, non-Indigenous students are required to have a non-English primary language. Indigenous students, by contrast, can be English-dominant or English monolingual. A critical question, therefore, is how EL classification impacts Indigenous students' educational outcomes. This study explores this question for Alaska Native students, drawing on data from five Alaska school districts. Using a regression discontinuity design, we find preliminary evidence that among students who score near the EL classification threshold in kindergarten, EL classification has a large negative impact on Alaska Native students' academic outcomes in the third and fourth grades. Negative impacts are not found for non-Alaska Native students.