That is a tough question to answer without having testing data. Does this child speak any English? Try some non-verbal activities with her where she has to point to things or choose things...anything that does not test her speaking/reading ability. If she still struggles with that it might be a mental or learning disability that would be taken care of with SPED services.

What about picture cards for vocabulary, or even starting at a lower grade level?? If this doesn't work, I would get in touch with your school psychologist and see about getting the student tested.

Depending on the assessment results, you might find answers to the students not progressing in reading. I wonder if you can reach out to the family and see if there is a specific topic that interests the student. If available, maybe you can allow her to do her reading on a tablet.

I think you should meet her where she stands, you know that she's reading at a first-grade level, so start there. Use flashcards, books that relate to things she's interested in or can relate to from her culture. Have the student teach the class about something from her culture. Have the class bring in their favorite book and do a classroom read aloud.

What level of SLA Proficiency is she? If she cannot speak, read, or write independently in English then it could possibly be that problem. If may also be an LD or lack of ESOL ELL classes and support of a bilingual assistant during her initial transition. I know the ELL students I work with they have a BLI or BLA for the first 2 years while transitioning into schooling in the USA.

This is a learning disability related to addressing her needs as an individual.