Between 2003 to 2015, multilingual students showed two to three times more progress in reading and math than students who speak English only. With this progress, the achievement gaps between multilingual students and their peers have narrowed substantially.

This new analysis we conducted of results from the National Assessment of Education Progress contradicts previous reports that academic progress has stalled for multilingual learners.

We make this observation as former teachers and researchers who have spent more than two decades focused on understanding the experiences of multilingual students.

Our findings not only show that multilingual students are learning more now than in the past, but they also suggest to us that schools and districts are serving these students more effectively.

Who are multilingual students?

Multilingual students include all students who speak a language other than English at home. About 1 in 5 children in the U.S. fall into this category.

Among multilingual students, one subgroup is English learners, who are not yet proficient in English. About 1 in 10 students in the U.S. is classified as an English learner.

A second subgroup is former English learners, who were not proficient in English when they entered school but have since developed English proficiency. No national data about the size of the former English learner population is available, but statewide data indicates that it’s slightly smaller in size than the current English learner population.

Finally, the third and smallest subgroup of multilingual students are those who speak a language other than English at home but who were already proficient in English when they started school.

Why our findings differ

Past analyses of data from the National Assessment of Education Progress – better known as NAEP – have focused only on outcomes for students currently classified as English learners. However, this produces misleading conclusions. By definition, English learners are not yet proficient in listening, speaking, reading or writing English, and their language skills impact their scores on reading and math tests. Once students become proficient in English and are able to perform at higher levels on these tests, they are no longer considered English learners. In other words, as soon as a student gains mastery, she is moved out of the English learners group. This has led researchers William M. Saunders and David J. Marcelletti, among others, to argue that the achievement difference between current English learners and other students on reading and math tests is a “gap that can’t go away.”

As research in New York City, two large California districts and other states demonstrates, many English learners become proficient in English between the time they enter school and when they are given the NAEP in fourth and eighth grades. These analyses indicate that about 25 to 50 percent of students who enter kindergarten as English learners have been reclassified as former English learners before grade four. Seventy to 85 percent of such students have been reclassified as former English learners before grade eight.

Thus, the current English learner group in these grades consists of those students who – by definition – have relatively low English test scores, either because they have recently immigrated to the U.S. or have struggled to acquire English language and literacy skills in U.S. schools.

We suggest that districts and states should analyze combined outcomes for both current and former English learners, which we refer to as the Ever English Learner subgroup. We have shown graduation rates for the full group of Ever English learners are quite similar to rates for students never classified as English learners.

Analyzing outcomes for Ever English Learners is not currently possible with NAEP data. Instead, in our new analysis, we took the most similar approach we could, analyzing outcomes for all multilingual students, which consists primarily of current and former English learners. We define multilingual broadly to include students at different levels of proficiency in their multiple languages. Given our prior work, we were not surprised to find that NAEP trends for multilingual students as a whole looked different than trends for current English learners. We were, however, surprised, by the extent of the progress multilingual students had made, given that this group has been historically and chronically underserved.

What’s behind the gains?

We cannot yet pinpoint the reasons why multilingual students have made such strong progress on NAEP. A variety of changes in education policy and practice have impacted multilingual students in recent years and may be related to these patterns. For example, the No Child Left Behind Act, which was implemented during the years we studied, may have increased attention to outcomes for English learners. In addition, these years also saw a rapid expansion of dual language immersion programs, in which multilingual students and monolingual English speakers learn alongside one another. Rigorous research has shown that these programs have positive effects on achievement for all students. In addition, many states have recently adopted new requirements for the preparation that teachers of English learners must have, and this additional preparation may increase teachers’ effectiveness with English learners.

Multilingual students still encounter many barriers in U.S. schools, including often having bilingualism treated as a problem rather than a resource. Yet our research suggests that nonetheless, multilingual students are demonstrating strong gains in reading and math. Understanding the reasons behind these gains will be critical to making sure the progress continues.

Karen D. Thompson receives funding from the U.S. Department of Education Institute of Education Sciences and the Spencer Foundation. In addition, Dr. Thompson and Dr. Kieffer's collaboration was made possible by the EL Policy Fellowship, with support from the Spencer Foundation and William T. Grant Foundation (Kenji Hakuta, PI).

Michael J Kieffer does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.