What is the 50/50 Model of Two Way Immersion (TWI)?
50/50: The partner language and English are used equally throughout the program. All students learn to
read in both languages starting in Kindergarten. Usually in the context of a 50/50 program Native English
speakers and native speakers of the partner language are integrated for instruction 100% of the day.
The ideal ratio of English learners to English speakers is 50:50 http://www.cal.org
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Teachers maintain separation of languages for instruction (no translation)
Skills taught in each language are coordinated to maximize cross-linguistic transfer and support
learning in content areas
Teachers use flexible grouping and differentiation to meet the needs of native speakers and
language learners.
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Two-Way Immersion 50/50 Model: Percentages of Daily Instruction
Grade
K and 1st
2nd
3rd
4th
5th- 6th
% of (L2)
50%
50%
50%
50%
50%
% of English
50%
50%
50%
50%
50%
What’s the difference between a 10/90 and 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.
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.
http://www.cde.ca.gov/sp/el/ip/faq.asp
Integrity of TWI/dual language model is preserved – all students receive 50% of instruction through both
languages at all grade levels and are integrated 100% of the time − Students learn literacy skills that
support the work they do in academic content areas in both languages − Literacy development in both
languages proceeds at a sufficientnpace so that language skills are sufficient to meet greater academic
demands in upper grades − Works with either a single teacher teaching both languages or one
teacher/one language approach.
http://www.cal.org/twi/initialliteracy.pdf