To observe a bilingual child's language fairly, teachers need to look at both languages together, not at each one separately. A child learning Vietnamese and English may know some words only in one language and some only in the other, may mix the two within a sentence, and may understand far more than she says. Good documentation records which language the child used, with whom and in what situation, notes understanding as well as speech, and draws conclusions only from a picture built across both languages and several weeks.
Bilingual children are often misjudged by assessment designed for monolingual children. Counted in one language only, their vocabulary can look small; heard in one setting only, they can seem quiet or confused. This article explains what research says about how bilingual children's language develops, how to set up observation in a Vietnamese and English classroom, and how to tell ordinary bilingual patterns apart from signs that a child may need a closer look. Methods for teaching in two languages are covered in this site's bilingual pedagogy category; this article is about watching and recording.
Why one-language assessment underestimates bilingual children
In the early 1990s Barbara Zurer Pearson, Sylvia Fernández and D. Kimbrough Oller studied the vocabulary of infants and toddlers growing up with English and Spanish in Miami. Counted in either language alone, the bilingual children's vocabularies tended to look smaller than those of monolingual children of the same age. Counted across both languages, as the total number of concepts a child could name in at least one language, they were comparable. The study is still widely cited because the lesson is so practical: if you measure only half of a bilingual child's language, you get half a picture.
The psycholinguist François Grosjean made the broader point that a bilingual person is not two monolinguals in one body. Bilinguals use their languages for different purposes, with different people and in different areas of life, so each language develops its own strengths. A child may know the words for food and family in Vietnamese, because that is the language of home and meals, and the words for colours and shapes in English, because that is how they were introduced at school. That pattern is not a gap; it is a map of her experience.
For teachers this means two things. First, every observation of language should record which language was used. Second, conclusions about a child's language should be drawn from both languages together, ideally by co-teachers who between them speak both.
Ordinary bilingual patterns and how to record them
Several features of bilingual development can look worrying to an adult who is not used to them. Most are entirely normal. The table describes the most common, what they usually mean and what a useful note looks like.
| Pattern | What it usually means | What to record |
|---|---|---|
| Mixing languages in one sentence | The child is using all the words she has; adult bilinguals do the same | The exact words, which language each part was in, and who she was speaking to |
| A quiet period in the new language | The child is listening and building understanding before speaking | Signs of understanding: following instructions, laughing at jokes, answering in the other language |
| Answering in Vietnamese to English questions | Understanding is ahead of speaking in English | The question, the answer, and whether the answer was appropriate |
| Uneven vocabulary across topics | Each language is tied to different settings and people | Which topics the child talks about in which language |
| Temporary drop in the home language | Exposure has shifted toward the school language | Family reports of home language use, plus school observations |
A quiet period in a new language can last weeks or months, and its length varies a great deal between children. This site's bilingual pedagogy category has a separate article on supporting children through it. For assessment, the key point is to record understanding, not only speech, so that a quiet child is not mistaken for a child who is not learning.
Building a language profile for each child
Observation is much more useful when teachers know something about the child's language background. A simple language profile, completed with the family when the child joins and updated once a year, gives that context. It records which languages are spoken at home and by whom, roughly how much time the child spends hearing each language, whether there are other languages in the family, such as a grandparent's language or a parent's third language, and what the family hopes for the child's languages.
The profile changes how observations are read. A child who hears English only at school will naturally use it less than a child with an English-speaking parent, and comparing the two would be meaningless. A child from a family where three languages are spoken may be juggling more than her classmates and deserves credit for it. An international family that has just moved to Vietnam may have a child who hears Vietnamese for the first time at school, and the team should expect Vietnamese to emerge slowly.
Families should be told why the school is asking and how the information will be used. Some parents worry that admitting the child speaks little English at home will count against her. The answer is the opposite: knowing this helps teachers interpret what they see accurately.
What to observe beyond vocabulary
Vocabulary is the easiest part of language to count and one of the least informative on its own. A fuller picture of a bilingual child's language includes the following, each of which can be observed in ordinary activity.
- Understanding. Does the child follow instructions, respond to stories and join in songs in each language, with or without gestures?
- Using language to get things done. Can she ask for help, negotiate a turn, protest, explain what she wants?
- Telling and explaining. Can she retell an event, describe how she built something or explain why something happened, in either language?
- Conversation. Does she take turns, stay on topic, ask questions, respond to others?
- Awareness of two languages. Does she choose a language depending on who she is talking to, translate for a friend, or play with words across languages?
- Early literacy. Does she show interest in books in both languages, recognise her name, make marks that she says mean something?
Awareness of two languages deserves special attention, because it is a strength that monolingual assessment never sees. A four-year-old who switches to English when the international teacher joins the table, or who explains a Vietnamese word to an English-speaking classmate, is showing sophisticated understanding of language and of other people. Notes like this belong in the language dimension of her record and often in the emotion dimension too.
Observing language across the settings of the day
Children use language very differently in different parts of the day, and a bilingual child's two languages may each have their own territory. Morning circle, led by one teacher in one language, is often where children are quietest, because they are speaking in front of the whole group. Free play, especially pretend play in the home corner, is often where language flows most freely, and where children try out phrases they would never risk at circle. Mealtimes bring out the language of food, requests and family routines. Outdoor time brings out the language of negotiation, rules and excitement.
A team that observes language only at circle or only during adult-led activities will form a narrow and often misleading picture. It is worth planning observation so that each child is heard in at least three or four different settings over a few weeks, and noting the setting in every language note. A simple grid of settings against languages, filled in over a theme, shows at a glance where each child is talking and where she is silent.
Peers matter as much as adults. Many children speak more English with a friend from an English-speaking family than with the international teacher, or more Vietnamese with a younger child they are looking after. Teachers who sit quietly near a pair of children playing often hear language they have never heard the child use with adults. Those moments are some of the most valuable evidence a language record can contain, and they are easy to miss if adults are always leading the talk.
Language difference or a sign of difficulty?
The question teachers worry about most is how to tell ordinary bilingual patterns from a real language difficulty. There is no simple rule, and teachers are not expected to diagnose. But some general principles are widely accepted among speech and language professionals. A genuine language disorder usually shows up in both languages, not only in the newer one. A child whose Vietnamese is developing well but whose English is still limited is most likely simply still learning English. A child who is struggling to understand and express herself in her strongest language, as well as in the other, may need a closer look.
Other signs that are worth discussing with the family, whatever languages the child speaks, include very limited understanding for the child's age, little interest in communicating through any means including gestures, loss of words or skills the child previously had, and speech that even familiar adults find very hard to understand at an age when most children are understood. None of these proves a difficulty, but each is a reason for a careful conversation and, if needed, specialist advice.
Bilingualism itself is not a cause of language disorders, and stopping one language is not a remedy. Families sometimes receive advice to drop the home language so the child can focus on English. Research on bilingual children with and without language difficulties does not support that advice, and losing the home language can cut a child off from her family. If a concern arises, the next step is an assessment by a qualified professional who can assess both languages, or who works with an interpreter.
Practical routines for a bilingual team
In a co-taught classroom, the Vietnamese and international teachers should divide language observation deliberately. Each records what she hears in her own language, and both note any mixing they notice. At the weekly planning meeting they compare notes on the same children, which quickly reveals children who are more confident in one language than the other and children who behave differently with each adult.
Short audio recordings are especially useful for language. A one-minute recording of a child retelling a favourite story in September and again in March, in whichever language she chooses, shows growth more clearly than any written note. Recordings should be stored securely according to the school's privacy policy and shared with the family as part of the portfolio.
In the Global Nexus curriculum, language is one of six dimensions of development, and observations are filed under it with the language noted. Vietnamese remains the anchor language for most children, so a child's Vietnamese is observed and supported as carefully as her English. The record never compares a child's English with that of her classmates; it describes how her two languages are growing together.
Câu hỏi thường gặp
Should a bilingual child's vocabulary be counted in each language separately?
It can be useful to know vocabulary in each language, but conclusions about overall language development should be based on both together. Research by Pearson and colleagues showed that bilingual toddlers' combined vocabulary is comparable to that of monolingual children.
Is it a problem when a child mixes Vietnamese and English in one sentence?
No. Mixing is a normal feature of bilingual development and of adult bilingual speech. It shows the child is using all the language resources she has. Teachers should record it, not correct it, and model each language naturally.
How long does the quiet period in a new language last?
It varies widely, from a few weeks to several months. During this time teachers should record signs of understanding, such as following instructions and responding appropriately, rather than judging the child by how much she speaks.
How can teachers tell a language difficulty from ordinary bilingual development?
A true language disorder usually affects both languages. If a child is developing well in her stronger language, limited speech in the newer one is most likely normal. Concerns about both languages should be discussed with the family and, if needed, a specialist.
Should families stop speaking their home language to help the child learn English?
Research does not support this advice. A strong home language supports learning a second one, and keeping it protects the child's relationships with family. Schools should encourage families to keep using the language they speak most comfortably.
Which teacher should record a bilingual child's language?
Both. Each teacher records what she hears in her own language and notes any mixing. Comparing notes during weekly planning gives a fuller picture than either teacher could form alone.