Summarizing the Research on Dual Language Learners

It’s impossible to have a conversation about dual language learners in the United States without being drawn into questions about their “difference,” and just how much it should be taken into account at school. For years, English-only advocates have argued that these differences should be ignored or erased, that we need to educate DLLs much as we educate monolingual English students — with English instruction. Others have suggested that we should treat the instruction of DLLs differently, but hold them to the same academic expectations as monolinguals. Still others argue that we should both treat DLLs’ classroom experiences differently and tailor our academic expectations to their different developmental trajectories.

At the end of the day, your mileage on any of these lenses for thinking about DLLs will probably vary according to your ideological commitments on language and American diversity. But research efforts are also advancing our knowledge of just how different DLLs’ linguistic and academic paths are. Whatever your preconceived notions, this research should inform the policies that govern DLLs’ educational experiences. The most recent edition of Early Childhood Research Quarterly (ECRQ) has several useful reviews of recent research on dual language learners.

I. In “The language and literacy development of young dual language learners: A critical review,” Temple University’s Carol Scheffner Hammer and her co-authors explore what we know about how DLLs learn to speak and read in both their home languages and in English. They surveyed nearly 200 studies on DLLs’ development and tried to condense the results into a summary of the field’s knowledge.

For instance, they found that the studies showed considerable variability between different groups of DLLs. That is, “[c]hildren vary with regard to their country of origin, the languages spoken, their experiences (both exposure and usage) with their two languages and their [socioeconomic status], among other characteristics.” This is an insight both critical and confounding. It’s relatively intuitive that the linguistic development of a Welsh-English DLL will be different from a Spanish-English DLL, and that — for instance — these differences might be relevant to how we approach early instruction to support each student’s phonological awareness in the early years.

So far, so good. But that intuition also presents pedagogical and political challenges. If DLLs’ developmental paths vary considerably within that student population, that makes it more difficult for teachers to tailor instruction to suit their needs, and for advocates to coalesce around a policy agenda that would better support them.

The researchers also found clear, growing evidence that “DLLs have two separate language systems very early in life.” That is, they build parallel language systems to support communication in both their first and second languages. There is some evidence (which I cite in my recent paper on state reclassification policies for DLLs) that development in one language can support the development of a second language. Furthermore, the development of DLLs’ bilingualism appears to depend somewhat on when they begin the process of learning each language.

II. A second ECRQ article, “Effects of early education programs and practices on the development and learning of dual language learners: A review of the literature,” synthesized 25 studies on dual language learners under the age of five. The University of North Carolina’s Virginia Buysse and co-authors explored the research on whether early education programs are particularly helpful for improving the linguistic and academic trajectories of DLLs.

The relatively small group of studies made it difficult to draw strong conclusions, but there were still some helpful patterns in the research. For instance, while the researchers were unable to find sufficient evidence to comment on the details of various early education program models (such as various approaches to language instruction like dual- or English-immersion programs), they did find “some evidence to suggest that DLLs may benefit from widely available early educational programs” like Head Start.

There were several small studies suggesting that “incorporating the home language into curriculum and instruction in early childhood” can be particularly good for DLLs, but the research is lacking to make this a consensus position. Indeed, Buysse and her co-authors found an odd pattern in the research that might contribute to the relative dearth of comprehensive information: Studies on the effects of English language early education programs for DLLs rarely measured how these programs affect DLLs’ home languages. By contrast, studies on the effects of programs that used both English and DLLs’ home languages generally include “measures in both English and the home language.” This asymmetry in research design means that we have less information than we might otherwise have on which early education programs work best for DLLs and that comparisons between research on these programs are more difficult.

The biggest finding of this article was clear: The community of researchers working on DLLs has yet to come to firm conclusions on some of the most controversial questions in their field.

It should go without saying that these two articles are extremely critical work in an era where literacy benchmarks are increasingly important. For instance, some states have set sharp rules linking third-grade English literacy to promotion to fourth grade. And this comes at a time in which most states are trying to raise their academic standards across the board. While the American education system could certainly do with higher expectations, this research suggests that these efforts need to carefully incorporate the specific needs of dual language learners.