The Next Generation Science Standards (NGSS) aim to engage all students in rigorous and equitable science learning. Among these students is a sizeable population of multilingual learners (MLs), who are learning science while simultaneously developing English proficiency. As the NGSS take hold in classrooms across the nation, science teachers and instructional designers are capitalizing on the affordances of local phenomena and science and engineering practices for engaging MLs in science. However, much less has been said about coherence—another key aspect of NGSS instruction—and its implications for this fast-growing student population.

This blog post addresses why coherence matters for MLs in science instruction. In coherent science instruction, lessons build on one another in a storyline toward the goal of explaining a phenomenon. Students drive the direction of their investigations based on what they’ve already learned and what they still need to figure out. While coherence enables all students to build and revise their science understanding over time, it could be especially crucial for MLs, who benefit from opportunities to engage in sustained and purposeful language use.

The importance of coherence from a language perspective first became apparent in my own life. Recently, I began watching television programs produced in Spain. Despite being a competent Spanish speaker in most situations, each time I start a new series, I struggle to understand the first few episodes and end up resorting to English subtitles. This difficulty stems in part from my lack of familiarity with the language associated with each program’s unique topic. But beyond the individual words, the more significant hurdle is grasping the “big picture”: who the characters are, how they relate, and what they are trying to accomplish. Once I orient myself to the show’s overall purpose, I can ditch the subtitles, and any unfamiliar language becomes much more manageable because I can fill in the gaps of what I don’t understand with what I do.

My experience watching Netflix will not be surprising to those familiar with foundational theories from the field of second language acquisition. One such theory is the theory of comprehensible input, which says that for language to be acquired, learners must receive messages in reading or listening (i.e., input) that are understandable to them (i.e., comprehensible). Because much of the input that the world provides can be incomprehensible, language learners benefit from sustained engagements with language input related to the same topic or theme. The idea is that language becomes more comprehensible over time, since learners have the advantage of the previous context to help them understand and acquire new language.

Other theories of second language acquisition place greater emphasis on its social nature. Specifically, these theories suggest that language learning occurs as a product of purposeful interaction in social contexts, such as classrooms. What makes interactions purposeful is that participants are collaborating on tasks that lead toward a shared purpose. Often these tasks involve some sort of information gap in which participants are missing some information they need to accomplish the task’s purpose and must therefore rely on one another and/or artifacts in their environment to exchange information that helps fill the gap. (Think of the information gap created by classic games, such as Guess Who?).

Together, these theories of second language acquisition help explain why coherence matters for MLs in science instruction. By offering a sustained focus on a phenomenon over multiple lessons, coherent science instruction is well suited to provide the comprehensible input MLs need to make sense of the language they hear and read in the science classroom, while also creating the conditions for them to acquire new language. Moreover, coherent science instruction fosters the kind of purposeful interaction known to facilitate language learning, as MLs are compelled to fill the gap between what they’ve already learned and what they still need to figure out about a phenomenon. Rather than start a new Netflix series with each lesson, MLs pick up on the plot right where they left off and engage with that plot as it develops.

Consider a fifth-grade science unit in which students are explaining the phenomenon of what happens to the garbage in their local community. Over nine weeks of instruction, MLs become familiar with language related to the phenomenon of garbage (e.g., landfill), which helps keep the instruction comprehensible while also creating the conditions for MLs to acquire new language as they build more sophisticated science understanding (e.g., “properties" to describe the different materials from the landfill that students are observing in their classroom). 

When the food materials start producing a funky odor, students ask, “What is that smell?” This question creates an information gap that subsequent investigations aim to fill through purposeful interactions among students and artifacts. As MLs weigh a balloon before and after it is inflated and compress air in a syringe, they exchange observations (e.g., “Something is in there!”) and clarify one another’s meanings (e.g., “What do you mean ‘something’?”) toward the shared purpose of making sense of what the smell is made of (i.e., gas particles). In this way, coherence from one lesson to the next becomes the fuel that propels purposeful interaction.

Science teachers and instructional designers are increasingly being asked, “What strategies do you use to support MLs in the science classroom?” This question typically elicits a menu of just-in-time strategies for MLs to engage in a particular lesson or moment in a lesson, such as sentence starters to participate in a class discussion or graphic organizers to write an argument. But lesson-level and moment-level strategies may not have much impact if science instruction lacks coherence at the unit level. In other words, if MLs encounter a deluge of incomprehensible input or have difficulty orienting to a lesson’s purpose, no sentence starter or graphic organizer is likely to ameliorate these challenges. Thus, recognizing the affordances of coherence for MLs must begin with expanding our conceptions of what “counts” as effective science instruction for this student population. Overall, by capitalizing on the affordances of coherence, teachers and instructional designers can make science as compelling and purposeful for MLs as our favorite Netflix series that makes us ask, “How about just one more episode?”

Scott E. Grapin is an assistant professor of language, literacy, and learning in the School of Education and Human Development at the University of Miami in Coral Gables, Florida. Broadly, his research centers on fostering equitable science learning environments for multilingual learners in K–12 education. Grapin is a member of the Science And Integrated Language (SAIL) research team who have been developing and implementing fifth-grade curriculum materials aligned to the NGSS in collaboration with teachers in linguistically diverse science classrooms. Grapin began his career in education as a high school English as a Second Language (ESL) and Spanish teacher in the New Jersey public schools.