How to Promote Additive Bilingualism over Subtractive Bilingualism in the Classroom


What’s the difference between additive and subtractive bilingualism? If you work with bilingual and English-language learning (ELL) children, the answer to this question could make a world of difference for your students. Teaching your ELL students additive bilingualism is one of the surest ways to help them gain strong reading skills in English, and in their first language too.

Read on to discover more about additive and subtractive bilingualism, as well as the many advantages of being bilingual. Then, learn how you can help your English-language learners maintain their first language (and why that matters).

Additive vs. Subtractive Bilingualism

If you’re trying to figure out the best way to support ELL children in the classroom, promoting additive bilingualism should be the goal whenever possible. But what is additive bilingualism, and what does it mean for ELL students?

First, here’s a quick definition of bilingualism in general. Bilingual refers to a person who can speak two languages fluently. Although some ELL students may not yet be fully bilingual, the goal for these students is to attain strong communication skills in English and in their first language.

Additive bilingualism is when a student’s first language continues to be developed while they’re learning their second language.[8] These students often have opportunities to use both languages inside and outside of school, and they have a desire to maintain both.[9] Additionally, if a child is from another culture, their first culture is also valued and respected in the classroom.

Subtractive bilingualism, however, is when a student learns a second language at the expense of their first language.[8] In this case, the child will usually lose the ability to speak their first language over time.[9] Children who develop subtractive bilingualism may not have opportunities to practice their first language and may even feel like their first language or culture is unwelcome in class.

If you do not speak a student’s first language or are unfamiliar with their first culture, you may feel unprepared to help them develop additive bilingualism. In this case, your role isn’t to directly teach in that first language, but to teach them core reading skills—like letter or sound recognition—that apply to both languages and to help them maintain a positive mindset towards their first language. You could, for example, stock your school library with a few books in their first language or connect them with other students who speak their language.

Recognizing the Many Benefits of Being Bilingual

Educators thought for decades that learning two languages at once would hinder a child’s literacy development.[14] Now, however, research has proven that this couldn’t be further from the truth. In fact, children who are bilingual often have an academic advantage compared to their monolingual peers. The cognitive benefits of being bilingual lead to skills that boost every aspect of a child’s academic career and impact the rest of their lives.

For example, bilingual students tend to perform better on tests that involve problem-solving ability or working memory.[7] They’re also better able to monitor and adapt to their environment, perhaps because these skills are necessary to understand and speak two separate languages.[15] These cognitive advantages last far beyond a child’s school years, and may even lower the chance of developing cognitive diseases like dementia.[13]

Additionally, bilingual children tend to have stronger social-emotional learning (SEL) skills. Research shows that they’re more skilled at conflict-resolution, which indicates that bilingualism strengthens overall communication skills.[10] Bilingual students also outperform their peers in self-control tests, meaning that they’re better able to regulate their thoughts, actions, and emotions.[14]

In all, bilingual children are more likely to have stronger skills in the following areas:

  • Problem-solving ability
  • Working memory
  • Self-control
  • Adaptation
  • Conflict resolution

While many bilingual children develop the benefits above, three factors correlate to stronger cognitive and social-emotional benefits. As expected, the level of proficiency in both languages and the length of time students have studied the second language both contribute to more and stronger benefits. Also, children with additive bilingualism are more likely to reap the cognitive benefits than children with subtractive bilingualism.[2] This means that the benefits of bilingualism aren’t only related to learning a second language, but also to maintaining the first language.

Prioritize Bilingualism and Biliteracy

Often educators of English-language learners exhibit a monolingual bias while teaching. This means that instead of prioritizing a proficiency in both English and the student’s first language, a teacher’s only goal is for the student to learn English.[3] However, when teachers encourage an additive bilingual education, their English-language learners are more likely to strengthen their reading abilities in both English and their first language.

Children who are biliterate also tend to have stronger overall reading skills compared to their peers, including:[15,16,17]

  • Letter decoding
  • Phonological awareness
  • Print knowledge
  • Metalinguistic awareness

This means that your strategy for English-language learners should be biliteracy. Biliteracy is here defined as the ability to read and write in two languages, in addition to oral communication skills in both. Research shows that if bilingual children are able to read and write in both languages they speak, they become more motivated to achieve in the classroom.[5]

Additionally, prioritizing biliteracy in the classroom also promotes intergenerational learning in both directions.[17] As dual-language learners develop English literacy, they may teach their families reading skills that they picked up in school. And vice-versa, parents may feel more comfortable reading to their child if they can do so in either English or their first language. All of this adds up to a greater engagement from parents in their child’s education and a greater learning environment at home. Also, teachers can involve parents in developing reading goals for both English and their first language, so parents can provide support for both from home.

How to Encourage Additive Bilingualism

Sometimes when dual-language learners enter a classroom, their first language skills suffer as the cost of learning English. As a teacher, you can help your students maintain additive bilingualism if you view their first language skills with a positive mindset.

Use these five tips and accommodations for reaching English-language learner students in a way that encourages additive bilingualism:

  • Encourage your bilingual students to develop biliteracy, or the ability to read in English and their first language, as well as bilingual speaking skills.[19]
  • Include parents in their child’s education and work with them to develop what they envision, in terms of their child’s bilingualism.[1]
  • If your bilingual student is still learning English, increase your wait time by 2–3 seconds when asking them questions.[18] It may take more time for these students to translate your question into their first language, then translate their answer into English.
  • Provide a training session for your teachers or colleagues on what additive bilingualism is and why to value it over subtractive bilingualism.[4]
  • Stock books in your bilingual students’ first language(s) to help them continue practicing their first language. Check out this list of bilingual children’s books from Scholastic to get started.


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  13. Craik, F.I.M., Bialystok, E., and Freedman, M. Delaying the onset of Alzheimer disease Bilingualism as a form of cognitive reserve. Neurology, November 2010, 75(19), pp. 1726-1729.
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