SEND Code of Practice clearly states (6.24)
“Identifying and assessing SEN for children or young people whose first language is not English requires particular care. Schools should look carefully at all aspects of a child or young person’s performance in different areas of learning and development or subjects to establish whether lack of progress is due to limitations in their command of English or if it arises from SEN or a disability. Difficulties related solely to limitations in English as an additional language are not SEN.”
Guidance
The Bell Foundation has guidance on assessing whether a pupil with EAL also has special educational needs.
The Bell Foundation also has assessment frameworks for both primary and secondary pupils to allow schools to assess oral language skills and reading and writing.