This article first appeared in TESOL Quarterly, Volume 46, Number 2, pgs. 334–361. Subscribers can access all issues for free here. TESOL members can subscribe to TESOL Quarterly here. To become a member of TESOL, please click here, and to purchase articles, please visit Wiley-Blackwell. © TESOL International Association.

Methods for second language education across the globe have adapted over time to deepen and broaden a learner's ability to use a new language. The deepening has sought to advance proficiency, and the broadening has added academic and other goals to social language abilities. Many changes have been derived from learner needs and interests as well as educators' explorations of better ways to teach. In the United States, however, another source for change is present. The educational reform movement, a political construct rather than a learner need, has had a direct impact on English language learner (ELL) education. States now implement high-stakes testing and standards-based instruction for all students, regardless of their proficiency in English. Classroom instruction is guided by mandated standards of proficiency for core subjects such as mathematics, science, and social studies, but in many content classes little or no accommodation is made for the specific language development needs of ELLs. This lack of accommodation raises a significant barrier to success, because ELLs are expected to achieve high academic standards in English and, in many states, must pass end-of-course tests or high school exit exams in order to graduate.

Unfortunately, ELLs in elementary and secondary schools have experienced persistent underachievement on the high-stakes accountability measures enacted as a result of the No Child Left Behind (NCLB) legislation passed by Congress. This legislation requires states to assess ELLs in English language proficiency annually; in mathematics and reading each year in Grades 3-8 and once in high school; and in science once in elementary, middle, and high school. As a result, a seventh-grade beginning-level ELL who has been in the United States for 1 year would take the same mathematics test in English as a seventh-grade native English speaker who has been in U.S. schools all his or her life. On nearly every measure of state and national assessments, ELLs lag behind their native-English-speaking peers and demonstrate significant achievement gaps (Kindler, 2002; Kober et al., 2006; National Center for Education Statistics,2009a, 2009b; Reardon & Galindo, 2009). These results are not unexpected, because most ELLs must take subject area tests using English before they are proficient in the new language.

Because these testing practices are unlikely to end soon, interventions for addressing the ELL performance gap are needed. One strategy is targeted teacher development, so that the resulting instruction provides ELLs with access to the core curriculum and concurrently develops their academic English proficiency in relation to that curriculum. The practice of integrating language development with techniques to make curricular topics more comprehensible to ELLs is generally known as sheltered instruction in the United States; this is when the main focus is on a specific subject curriculum and the instructor is a content specialist. It is referred to as content-based English as a second language (ESL) when the main focus is on language learning and the instructor is a language specialist (Crandall, 1993; Short, 2006; Snow, Met, & Genesee, 1989). Content-based language instruction is applied internationally in foreign and second language settings (including postsecondary institutions) for language minority and majority students. It is similar to content and language integrated learning (CLIL), sustained content language teaching, English for specific purposes, and other labels (Lyster, 2007; Mohan, Leung, & Davison, 2001; Murphy & Stoller, 2001; Stoller, 2004). In the United States, it involves second language learners (usually minority language speakers) who are studying content in the new language (usually the majority language), which is the medium of instruction.

As methods for integrating language and content instruction have developed over the past two decades, many combinations of techniques have been applied to the delivery of sheltered instruction and content-based language instruction. The study presented in this article investigated one particular approach of sheltered instruction, known as the Sheltered Instruction Observation Protocol (SIOP) model. The SIOP model offers a system for lesson planning and delivery that incorporates best practices for teaching academic English and provides teachers with a coherent method for improving the student achievement. Teachers integrate instruction of content concepts with academic language in order to develop student skills in reading, writing, listening, and speaking. The concepts and language skills are aligned to state proficiency standards, and teachers use techniques designed to make academic topics accessible to students and to enable them to practice the use of academic language as it is employed in each subject area.

SIOP Model Development and Research

SIOP began as an observation tool for researchers to measure teachers' implementation of sheltered instruction techniques. It evolved into a lesson planning and delivery approach, known as the SIOP model, through a 7-year research study sponsored by the Center for Research on Education, Diversity and Excellence (CREDE) and funded by the U.S. Department of Education. It began in 1996 and involved teams of researchers and middle school teachers in three school districts. At that time, there was no model of sheltered instruction. Instead, teachers selected from a wide range of techniques and activities to design lessons as they chose. As a result, sheltered instruction varied widely across schools and within different classrooms in the same school.

Our goal was to create and test a model that teachers could implement with consistency and with the knowledge that doing so would improve student performance…

This article first appeared in TESOL Quarterly, 46, 334–361. For permission to use this article, please go to http://www.copyright.com/.
doi: 10.1002/tesq.20