Bilingual education is a fairly broad term, and while journal articles including bilingual education are plentiful, finding the kinds of articles you need can involved a lot of sifting. Included here are some key words that should help you narrow your search.
English Language Learners
English as a Second Language
Bilingual AND Assessment
Bilingual AND Instruction
It may also be helpful to know that there are several different methods for teaching English learners, and many articles will support or criticize a particular method.
You may also find it helpful to limit your results to articles published in the last few years, although much of the scholarship on this topic, especially about students who primarily speak Spanish, is recent.
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