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Multilingual FAQ

Multiligual Education frequently asked questions on instructional approaches and other issues.

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What is the difference between a 90:10 and a 50:50 model?

The first number refers to the amount of instructional time initially spent for instruction in the target or non-English language in kindergarten. The second number refers to English. In a 90:10 model the amount of the target language decreases yearly as English increases until there is a 50:50 balance of the languages generally in grades four through six. A 50:50 model uses English and the target language for 50 percent of the time throughout the duration of the program.

Why is it okay to immerse English speakers in a language, but not Spanish speakers?

The English speaker is not at risk of losing the English language. English is spoken at home, in the community, and in the media. Dual-language immersion programs are not replacing English with another language, but provide the students the opportunity to acquire a second language. Dual-language immersion programs are additive programs in that a second language is acquired while maintaining the first language of the students.

Which model is more effective - 50:50 or 90:10?

Regardless of the model implemented, both models have been found to effectively achieve the goals of bilingualism and biliteracy; however, the 90:10 model has been shown to create higher levels of bilingualism. For specific research studies, consult the Center for Applied Linguistics External link opens in new window or tab. FAQs.

Can you implement a dual-language immersion program with a school population of 96 percent Spanish speakers?

No, the ideal ratio of English learners to English speakers is 50:50, but to stay within the program design, the recommendation of many practitioners is that the ratio should never go below 33 percent for either language group. A school may however, under certain circumstances, choose to select a developmental bilingual (maintenance) or heritage language model for developing bilingualism for this population.

What are the criteria for students to be in a dual-language immersion program?

There are no specific criteria for students except parental choice.

Can you include English learners of a language other than Spanish in a Spanish/English dual-language immersion program?

English learners in a Spanish/English dual-language immersion program should be Spanish speakers. However, speakers of other languages who are proficient in either Spanish or English could be eligible for enrollment in the program.

Must you have parallel materials in both languages in the content areas?

No, materials are acquired according to the language of instruction of the content area. For example, if the decision is made to teach math in Chinese and social studies in English, then the mathematics materials should be in Chinese and the social studies materials should be in English. The difference is in the language of delivery, not the content.

Does it cost more to implement a dual-language immersion program?

Not necessarily. However, many successful programs have found that some extra funding is necessary to provide staff development and purchase materials in the target language, especially for library and research materials.

How is a dual-language immersion program integrated with other programs at a school site?

The dual-language immersion program should not be viewed as a separate program. The school should develop a common vision of equity for all students that values the students language and culture. The same standards-based curriculum is taught in the dual-language immersion program that is taught in other school programs. Staff development should be provided for all staff so that the philosophy and program goals are shared. Sufficient time must also be allocated to the specific needs of the dual-language program staff.

How can "quality control?" be maintained in a dual-language immersion program?

Ongoing monitoring of the program is very important. Time should be allocated for teachers to meet in grade-level groups and across grades to discuss program design issues and to interpret student data. These sessions can be facilitated by an administrator, resource teacher, or designated lead teacher who is knowledgeable in dual-language immersion program design and instruction.

Do you need two teachers per classroom to implement a dual-language immersion program?

No, one teacher who is proficient in the target language and English can successfully implement a dual-language immersion program in the classroom. It is recommended, however, that teachers team teach for the language blocks of instruction, especially in the primary (kindergarten through second) grades so that students identify with a target language speaking model and an English-speaking model.

It is advantageous that during the first couple of years of the program, particularly during English instruction, teachers who understand the target language are used so that they can communicate with the target language speakers.

Do English learners get enough English instruction in a 90:10 model?

English time must be carefully defined and implemented. High quality curriculum and instruction are essential. Research shows that when programs are fully implemented according to the program design, English learners in 90:10 models score as well as or better than their peers in other programs in English tests. (Lindholm-Leary, (2001) Dual Language Education, Multilingual Matters LTD)

How can students who speak only English learn when they are instructed for up to 90 percent of the day in a language they don't understand?

Understanding or reviewing the research on which these programs are based best answers this question. Dual-language immersion programs are based on years of research from the foreign language immersion models in Canada designed for English speakers learning French. This model, in which English-speaking students have been instructed in French for up to 100 percent of their day, shows students perform as well as or better on tests of English than their English-speaking peers who have been instructed only in English. For more information on immersion programs, visit the Center for Advanced Research on Language Acquisition External link opens in new window or tab.. Fifteen years of results on dual-language immersion programs show similar results.

Where can I get more information on dual-language immersion programs?

Two of the most extensive Web sites on dual-language immersion programs are the Center for Applied Linguistics External link opens in new window or tab. and the National Clearinghouse for English Language Acquisition and Language Instruction Education External link opens in new window or tab. .

Questions:   Language Policy and Leadership Office | 916-319-0845
Last Reviewed: Friday, December 22, 2023
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