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December 1, 2004

The Rich Promise of Two-Way Immersion

Two-way bilingual immersion programs go beyond language proficiency to give students academic confidence and broader cultural awareness.
The Rich Promise of Two-Way Immersion- thumbnail
Credit: © Stefanie Felix
Two-way bilingual immersion education has great potential to promote skills that students will need for the changing global job market and to help eradicate the achievement gap between native English-speaking and English language-learning students. Two-way programs successfully educate native English speakers and English language learners within the same classroom and fulfill for both groups the goals of full bilingualism and biliteracy, grade-level academic achievement, and multicultural competency.
  • The demographic landscape of the United States is changing—and so is the job outlook. We are rapidly becoming a country of many languages. The Latino population in the United States, for example, is expected to reach 24 percent of the general population by 2050, and the Asian American population will represent 10 percent of the population by 2050. An ever-increasing percentage of students enter school not proficient in English.
  • Bilingual education leads to academic achievement. Research clearly shows that students in bilingual programs can develop academic skills on a par with, or superior to, the skills of comparison groups of their peers educated in English-only classrooms (Genesee, Lindholm-Leary, Saunders, & Christian, in press; Howard, Sugarman, & Christian, 2003). Some research findings even show that highly bilingual students reach higher levels of academic and cognitive functioning than do monolingual students or students with poor bilingual skills. In addition, students who are bilingual will have skills that enable them to take advantage of more career opportunities (August & Hakuta, 1997).

Two-Way Bilingual Immersion Defined

  • Instruction and classwork take place in two languages, with the non-English language used for at least 50 percent of the students' instructional day.
  • The day includes periods of instruction during which students and teachers use only one language, with no translation or language mixing allowed.
  • Both English language learners and native English speakers do work in both languages in a balanced proportion.
  • English language learners and native English speakers are together for most content instruction.
The major goals of TWBI programs are for students to develop high levels of oral language skills and literacy in both English and the non-English language, attain academic achievement at or above grade level as measured in both languages, hold positive attitudes toward school and themselves, and exhibit knowledge about and positive attitudes toward other cultures.
Two-way bilingual immersion programs have surged in popularity in the United States. In 1987 only 37 TWBI programs operated in public schools in this country; currently, about 320 such programs exist in 25 U.S. states and in Washington, D.C., with new programs added every year. Approximately 79,000 U.S. students study in dual language programs (about half of them ELLs and half native English speakers), and in the next five years enrollment may reach 100,000. Although most of the programs are Spanish/English, other languages in the programs include Chinese, Korean, French, Portuguese, and Navajo.

Two Models of Instruction

There are two common instructional designs in TWBI programs: 90:10 and 50:50. The allotment of time for instruction in each language varies across the grade levels in the 90:10 design but not in the 50:50. In the 90:10 model, students in kindergarten and 1st grade spend 90 percent of their instructional day with content delivered through the target, or non-English, language. Ten percent of the day is devoted to instruction in English that focuses on oral language proficiency. Reading instruction begins in the target language for native speakers of both languages.
In 2nd and 3rd grade, students spend 80 percent of their class time using the target language and 20 percent using English. As in the previous grade levels, most content is taught in the target language. In 2nd grade, English time is still largely devoted to developing students' preliteracy skills and academic language proficiency; students begin formal English reading in 3rd grade. In 4th and 5th grade, instructional time is balanced equally between English and the target language.
Unlike the 90:10 model, the 50:50 model evenly divides instructional time between the two languages across all grade levels. There are variations within this model, however. In the 50:50 simultaneous model, reading instruction in both languages starts in kindergarten; in the 50:50 successive model, each student initially receives reading instruction in his or her native language and begins reading instruction in the second language in 3rd grade.
For both the 90:10 model and the 50:50 model, the content areas taught in each language depend on the available curriculum and resource materials and on particular needs at each school site. However, teachers in both models attempt to give students the chance to develop academic language in all of the major curricular areas.

Factors for Success

A substantial body of literature shows similarities between the characteristics of exemplary two-way bilingual immersion programs and those of effective mainstream programs. A review of the research reveals six factors that influence the achievement of linguistically diverse students in bilingual programs (Lindholm-Leary, 2001).
School environment. A cohesive, schoolwide vision with clearly defined goals for student achievement enhances student outcomes. Administrators of bilingual immersion programs must establish faculty cohesion and collaboration within the school. In schools with a separate TWBI program, non-TWBI teachers should be informed about and urged to support the bilingual program.
Curriculum and instruction. Any effective curriculum must be clearly aligned with standards and assessment and must be both meaningful and academically challenging. The curriculum for a bilingual immersion program should integrate language instruction within the overall curriculum and foster use of both languages across the curriculum. The curriculum needs to reflect and value the cultures of all students involved, and it must provide structured and unstructured opportunities for students to speak both languages.
Program planning. A strong program-planning process should include proper scope, sequence, and alignment with developmentally appropriate practices and language proficiency levels in both languages. If the two-way bilingual program is a strand within the school, then planning for the program should be schoolwide and include non-TWBI teachers.
Assessment and accountability. TWBI education programs should use multiple measures in both languages to assess students' progress toward bilingual and biliteracy goals, along with the curricular and content-related goals.
Teacher quality and familiarity with bilingual education. High-quality teachers are vital to effective TWBI programs. Teachers must be familiar with the immersion model and with appropriate instructional strategies, and they must understand theories underlying bilingual education, second-language development, cooperative learning, assessment, and education equity. Ideally, they should be fluent in both languages.
Family involvement. Effective programs create an environment in which parents from all linguistic and cultural backgrounds feel valued and welcome. English-speaking parents should not dominate parent advisory groups to the exclusion of the non-English-proficient parents.

Rewarding Outcomes

Language Proficiency

Several studies of 5th and 6th grade students who attended a two-way bilingual immersion program since kindergarten or 1st grade show that both native English-speaking and English language-learning students became proficient in both languages (Christian et al., 1997; Howard, Christian, & Genesee, 2003; Howard, Sugarman, & Christian, 2003). In one high school, almost all TWBI students who took the Spanish advanced placement test scored high enough to earn advanced placement credit, although native Spanish speakers had higher levels of Spanish proficiency than native English speakers did. Students in 90:10 programs tend to be more fully bilingual than students in 50:50 programs (Lindholm-Leary, 2001). Despite receiving less exposure to English during their instructional day, ELLs in 90:10 programs were as likely to be proficient in English as ELLs in the 50:50 programs were.

Reading and Writing

Two studies examining the English and Spanish reading and writing proficiency of upper-grade elementary students in Spanish/English bilingual immersion programs indicate that both groups of students progressed to high levels of reading and writing ability in both languages in composition, grammar, and mechanics (Howard, Christian, & Genesee, 2003; Serrano & Howard, 2003). Although essay-writing scores in English were similar for ELLs and native English-speaking students, ELLs tended to write more sophisticated essays in Spanish than native English speakers did. Students tended to be stronger in their first language, although the gap between ELLs' knowledge of their first and second languages was smaller. Some measures indicated that native Spanish speakers ended up with stronger writing skills in English than in Spanish.

Academic Achievement

  • Both English language learners and native English speakers in bilingual immersion programs demonstrated large gains over time in their reading and math achievement test scores.
  • By middle school, both groups scored at or well above grade level in reading and math when measured in both languages.
  • By 5th grade, both groups showed academic achievement at comparable or superior levels to the achievement of peers who spoke the same native language but had not gone through a bilingual immersion program.
As Figure 1 illustrates, on norm-referenced standardized tests of reading and math achievement in English, native English-speaking 7th graders in California who had completed a two-way bilingual immersion program scored above the state average for 7th graders. Students who started out as English language learners and studied through bilingual immersion not only scored significantly higher than ELLs educated in English-only classrooms but also performed on a par with native English speakers educated in English-only classrooms (Lindholm-Leary, 2004; Lindholm-Leary & Borsato, 2004, in press). Studies of youth in Chinese and Korean immersion programs yielded similar results (Lindholm-Leary, 2001).

Figure 1. Achievement of 7th Graders in Two-Way Bilingual Immersion (TWBI) Programs

By 8th grade, ELLs educated through two-way bilingual immersion programs scored comparably to native English speakers on tests in English, regardless of whether they had participated in 90:10, 50:50 simultaneous, or 50:50 successive programs. When achievement was measured in Spanish, students in 90:10 programs received higher marks than did students in 50:50 programs (Lindholm-Leary, 2004).

Attitudes Toward School

Secondary students who studied within either a 90:10 or a 50:50 bilingual immersion program in elementary school have expressed very positive attitudes toward school and their programs (Cazabon et al., 1998; Lindholm-Leary, 2001; Lindholm-Leary & Borsato, 2001). Most students believed that learning through two languages trained them to think better and helped them do better in school. Latino students especially gave positive responses; most felt valued in the immersion program, were glad they had participated in it, and would recommend it to other students. The majority of students believed that participating in a bilingual immersion program challenged them more, gave them more confidence, and gave them a better education than a standard school model would have done—and again, Latino students expressed this view more strongly than others.
The national high school dropout rate of Latino students (30 percent) is twice the rate of that for African Americans and three times the rate of that for European Americans, and it is increasing. In one study of Latino high school students with past experience or current enrollment in TWBI programs in California, 87 percent of 9th and 10th graders and 93 percent of 11th and 12th graders interviewed said they would not drop out of school. Of those who had considered dropping out, most said they would remain in school because they needed an education. Almost one-half of English language-learning Latino students and one-third of native English-speaking Latino students credited the program with keeping them in school (Lindholm-Leary & Borsato, 2001).
The TWBI model represents one of the best teaching practices available to address the cultural, ethnic, and linguistic diversity in today's classrooms. These programs turn a landscape of inequality for English language learners and frustration for many teachers into a win-win situation for both schools and students. Not only is academic achievement boosted for all, but U.S. students also gain skills to survive and thrive in a country of many cultures.

August, D., & Hakuta, K. (1997). Improving schooling for language-minority children: A research agenda. Washington, DC: National Academy Press.

Cazabon, M., Nicoladis, E., & Lambert, W. E. (1998). Becoming bilingual in the Amigos two-way immersion program. Santa Cruz, CA: Center for Research on Education, Diversity & Excellence.

Christian, D., Montone, C., Lindholm, K. J., & Carranza, I. (1997). Profiles in two-way bilingual education. Washington, DC: ERIC Clearinghouse.

Collier, V. P., & Thomas, W. P. (2004). The astounding effectiveness of dual language education for all. NABE Journal of Research and Practice, 2(1), 1–20.

Genesee, F., Lindholm-Leary, K. J., Saunders, W., & Christian, D. (in press). Educating English language learners: A synthesis of empirical evidence. New York: Cambridge University Press.

Howard, E. R., Christian, D., & Genesee, F. (2003). The development of bilingualism and biliteracy from grades 3 to 5: A summary of findings from the CAL/CREDE study of two-way immersion education (Research Report). Santa Cruz, CA & Washington, DC: Center for Research on Education, Diversity & Excellence & Center for Applied Linguistics.

Howard, E. R., Sugarman, J., & Christian, D. (2003). Trends in two-way immersion education: A review of the research. Washington, DC: Center for Applied Linguistics.

Lindholm-Leary, K. J. (2001). Dual language education. Avon, UK: Multilingual Matters.

Lindholm-Leary, K. J. (2004). Biliteracy issues and outcomes in different models of dual language programs. Paper presented at the 13th Annual Illinois Reading Recovery/Descubriendo La Lectura Institute, Chicago, Illinois.

Lindholm-Leary, K. J. (in press). Review of research and best practices on effective features of dual language education programs. In L. Howard, K. J. Lindholm-Leary, J. Sugarman, D. Christian, & D. Rogers, Guiding principles for dual language education. Washington, DC: U.S. Department of Education & National Clearinghouse for English Language Acquisition.

Lindholm-Leary, K. J., & Borsato, G. (2001). Impact of two-way bilingual elementary programs on students' attitudes toward school and college. Research Report 10. Santa Cruz, CA: University of California, Center for Research on Education, Diversity & Excellence.

Lindholm-Leary, K. J., & Borsato, G. (2004). Mathematics achievement of middle-school Hispanic students participating in two-way bilingual programs. Paper presented at the American Educational Research Association annual meeting, San Diego, California.

Lindholm-Leary, K. J., & Borsato, G. (in press). Academic achievement. In F. Genesee, K. J. Lindholm-Leary, W. Saunders, & D. Christian (Eds.), Educating English language learners: A synthesis of empirical evidence. New York: Cambridge.

Serrano, R., & Howard, E. R. (2003). Maintaining Spanish proficiency in the United States. In L. Sayahi (Ed.), Selected proceedings of the first workshop on Spanish sociolinguistics(pp. 77–88). Somerville, MA: Cascadilla Proceedings Project.

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