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The Real Impact of ‘English Only’: Lessons for EAL Educators

20TH JUNE 2025

Why school leaders need evidence-based language policies

In this honest, authentic blog Adam Lewis (EAL teacher at The British International School, Hanoi) reflects on how EAL teaching guidelines have changed over the course of his career.

From banning students speaking their first language in the classroom, to actively encouraging students to explore their multilingual skills, Adam has taught on both sides.

His first-person experience is insightful, interesting, and rooted in research. He calls for school leaders to create consistent, research-led language policies to enable EAL learners to thrive, but to also maximise EAL teachers’ impact.

Why I thought ‘English Only’ was the best approach for EAL learners

Let me start with a confession: I have spent a significant amount of my eleven years as a primary school EAL teacher in Vietnam demanding that all students speak only English during my lessons.

In my very early career, I worked as a Grade 5 language assistant with an experienced American teacher in an American international school. One of his five classroom rules, repeated daily by the children who were mostly from South Korea, was to ‘only speak English’. I figured that if it was good enough for him then it was good enough for me. When I graduated to teaching my own classes I ‘magpied’ his classroom rules. The verb ‘to magpie’ in this context essentially means ‘pedagogic theft’. Apparently, larceny is ok when a magpie does it.

In following his lead, I also began to insist that students only ever use English during our lessons. I continued to do so for the best part of the next eight years. My ‘English only’ policy was a good fit for the Vietnamese bilingual schools I went on to teach in, where the core assumption was that the best way to learn English, and to learn in English, was to use English only. I asked my students to leave their home language at the door. This assumption became, as so many assumptions do, an unquestioned orthodoxy. Of course, students shouldn’t use their home language. How will their English improve if they’re speaking Vietnamese?

I reflect now and understand that I was wrong to insist that the students’ home languages should be outlawed in my classrooms. This is certainly not my approach now.

Why do EAL teachers prohibit home languages in the classroom?

When there is no explicit language policy in a school, teachers are left to make their own pedagogical choices.

Some research suggests teachers believe “English only” prepares their students for success. Students are likely working towards national assessments such as SATs and GCSEs. Since these assessments are carried out in English, then it ‘makes sense’ that students learn entirely in English.

Classroom management is another common reason for prohibiting other languages. A monolingual teacher can’t be sure a student is on task and working well if the student is speaking a different language. Consciously or subconsciously, some teachers fear that by encouraging pupils to use their own languages, classroom behaviour could become unmanageable.

Whatever the reasoning behind the ‘English only’ approach, we now know that it is not the best practice for EAL teaching. Working with a learner’s home language as much as possible is key to language acquisition

Doing things differently: what the research says

The research is overwhelmingly in favour of using home languages for learning.

Hamish Chalmers has even noted that the question is no longer ‘whether’ we should use home languages, but rather ‘how’ to use them. I have come to understand this only embarrassingly recently in my career. Sure, better late than never, but I reflect now on how much more effective my instruction could have been if I’d done things a little differently.

The research suggests that teachers in English-speaking schools, more often than not, don’t know what to do when it comes to handling languages. There is a whole spectrum of approaches available to us, from encouraging students to use their languages freely to demanding that they use only English, and it seems that teachers are all doing things differently. Language policies can even be inconsistent within the same school. Across EAL education, schools should set EAL teachers up for success by implementing research-informed languages policies.

How can school leaders improve EAL provision in their school?

It falls on school leaders to set clear guidelines for their teachers to follow. My own journey from ‘English only’ to ‘multilingual leveraging’ makes me sure that so much is possible, but only once educators (teachers and those who lead them) are properly informed.

To be clear, what I’m proposing here is not a free-for-all. This isn’t me saying to my students ‘say whatever you want, whenever you want, in whatever language you want, and it’s cool’. There remain times when a teacher might, for strategic reasons, ask students to rely only on English, perhaps caveating that request with ‘as far as possible’. Teachers may encourage students to combine their first language strategically with English to maximise their academic output, a practice better known as translanguaging.

The key word is strategic.

A strategic approach to languages in the classroom would be one that enables students to rely on whichever language resources they have to complete tasks. This is no small ask. It will require teachers to be equipped with the knowledge (i.e., the research) and the ability (i.e., the practical skills) to do so. And, that’s where all of this becomes a wider school responsibility. Because, as I’ve learned from my own life as a teacher, leaving it to the teachers to find out for themselves really isn’t an option.

Working together on research-led approaches to EAL.

It’s clear that school leaders have an immense opportunity to affect the delivery of EAL teaching in their school, and I encourage all school leaders to engage with research-led practices. However, I do acknowledge the responsibility for successful EAL teaching isn’t entirely on school leaders.

There should be more emphasis on research around the benefits of multilingualism in the classroom at the teacher training stage. Equipping new teachers with the best strategies for EAL teaching will positively affect EAL education and EAL students for years to come.

Finally, experienced EAL teachers such as myself bear responsibility too. Just as I ‘magpied’ my teaching strategies at the start of my career from a teacher I looked up to, other teachers will now be looking to me for guidance. I know how vital multilingual EAL teaching is, and so I advocate for better language policies and champion research-led approaches in my classroom and across the school.

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