A study by Saldate, Mishra and Medina (1985) compared programs in Douglas, Arizona, a city on the Mexican border in which a great deal of Spanish is spoken. Bilingual education students were all from one school whose enrollment was nearly entirely Mexican-American. Comparison subjects were from other schools, “whose enrollment ranged from 60 to 90 percent” Mexican-American (p. 26). While bilingual education students were described as “low socio-economic,” there was no description of comparison students, but Saldate et. al. note that in the study, pairs of students from each group were matched on the basis of the Peabody Picture Vocabulary Test.
The description of the bilingual program was provided in Medina, Saldate and Mishra (1985), a follow up study discussed below. For subject matter, the “preview-review” method was used in which material is presented in one language and then reviewed in the other, followed by another review in the first language. Spanish reading and ESL was also included. According the Medina et. al., the first language was used 90% of the time in grade 1, 80% in grade 2, and 50% in grade 3. Also, by grade 3, alternate-day instruction was introduced for subject-matter teaching.
Children were tested at the end of grade 2 on the Metropolitan Achievement Tests and at the end of grade 3 on the Wide Range Achievement Tests. For the WRAT, scores for English reading are presented here, a test that emphasizes word recognition and decoding. As shown in Table 2, the comparison group did slightly better than the bilingual education students in grade 2, but differences were small and not statistically significant. In grade 3, the bilingual education students outperformed the comparison students; here the difference was statistically significant and quite large. These results should be interpreted cautiously, however, because of the small sample size and the fact that the grade 3 sample was reduced from grade 2. Still, they are impressive.
Table 2: English reading performance of students in bilingual vs. nonbilingual programs (Saldate, Mishra and Medina, 1985)
The results of these two studies are fully consistent with the results of studies done elsewhere. Greene (1997), for example, concluded that the use of the native language in instructing limited English proficient children has “moderate beneficial effects” and that “efforts to eliminate the use of the native language in instruction ... harm children by denying them access to beneficial approaches.”
The next two studies examine the progress of graduates of bilingual education.
Medina, Saldate and Mishra (1985) is a follow-up of Saldate et. al. (1985). Subjects were graduates of the bilingual program described in Saldate et. al. (but were not the same children examined in that study), and had received bilingual education up to grade six. After grade six, instruction was all in English. All subjects in both the experimental and control group had graduated high school "on schedule." In both the experimental and comparison groups, all who remained to graduate on schedule were tested: in the bilingual group, 19 out an original 136 (14%), and in the comparison group, 24 out of an original 136 (18%) – nearly identical percentages. The results of tests administered in grades 6, 8 and 12 are presented in Table 3. There were no significant differences between the groups at any of the levels, although the comparisons did slightly better. Note that at grade 12, both groups were near national norms. Once again, sample sizes were quite small.
Table 3. Long-term performance of graduates of bilingual vs. nonbilingual programs (Medina, Saldate, and Mishra, 1985)
MAT = Metropolitan Achievement Test
Powers (1978) studied the progress of graduates of bilingual education in Nogales. Students were tested at grade 5 on the Stanford Reading Test and at grade 7 on the Gates-MacGinitie Reading Test. We have little description of the bilingual program; we know only that students in the study had been in bilingual education for three to five years, and that in grade 1 85% of instruction was in Spanish, and in grades 4 and 5, 30% was in Spanish. Comparison students were Mexican-American students who did not receive any bilingual education.
Table 4 presents mean scores for bilingual education graduates and comparison graduates, adjusted for socio-economic factors. Comparison studies did better than students in bilingual education in grade 5, but this difference was reduced by grade 7, and was not statistically significant.
Table 4: Adjusted means for tests of reading comprehension, bilingual vs. nonbilingual graduates (Powers, 1978)
Powers also presented evidence that students who reported more English use at home on entry to school and at grade seven had higher reading scores. Of crucial importance is the fact that comparison students reported more English use. This factor, however, was not controlled in the analysis.
The results of this study are only suggestive: An important control, English use outside of school, was not included and we have no description of the bilingual program. These factors could act to underestimate the effect of bilingual education.
In studies done outside of Arizona, graduates of bilingual education have been shown to do very well, sometimes outperforming native speakers of English in their districts (Burnham- Massey and Pina, 1985; San Francisco USD, 1998). In the two Arizona studies involving graduates reviewed here, bilingual education graduates also did well, achieving close to national norms in one case, and doing only slightly worse than comparisons in another case, despite using less English outside of school.
These results do not support the view that bilingual education in Arizona is a failure. In fact, Arizona studies strongly suggest that bilingual education is beneficial, a conclusion that is consistent with the results of studies done in other states. What is clear is that calls for the elimination of bilingual education are completely unjustified.
The results presented here probably underestimate the positive effects of bilingual education. We have little information about the details of the bilingual education programs, and what details are provided suggest that the programs were not set up in an optimal way (Krashen, 1996). One would expect that bilingual programs that are better implemented would produce even stronger results. We have learned a great deal since the 1970s and 1980s.
Table 5. LEP student performance on Stanford 9 reading test, bilingual vs. English-only programs in Arizona, 1998-99
Mean scores are given in NCE’s (normal curve equivalents).
Acknowledgment: We thank David McField for his encouragement and assistance.