Research

Introduction

Membean is a curated framework of best practices to systematically teach vocabulary and foster word consciousness. Where possible, we incorporate best practices from published quantitative studies on both vocabulary and learning. Where quantitative research is unavailable, we draw from qualitative studies. In areas lacking formal research, we synthesize published expert opinions from vocabulary and learning researchers, balanced with practical insights on vocabulary instruction from frontline classroom teachers.

Why Vocabulary Instruction is Important

While the exact complex relationship between vocabulary and reading comprehension is not fully understood, there is little doubt that vocabulary knowledge is one of the strongest predictors of reading comprehension, with correlations ranging from 0.6 to 0.93 (Jeon & Yamashita, 2022; Pearson, Hiebert, & Kamil, 2007, Nagy & Stahl, 2006).

Limited vocabulary puts disadvantaged students at greater academic risk through “Matthew Effects” (Stanovich, 1986), where early gaps in word knowledge grow larger over time. Merely attending school doesn't guarantee vocabulary growth (Cantalini, 1987; Morrison, Williams, & Massetti, 1998), and without intervention, vocabulary gaps typically persist across grades (Biemiller, 2001; Hart & Risley, 1995; Catts, Adlof, & Weismer, 2006). Despite this, it is particularly concerning that studies have repeatedly documented little vocabulary instruction in schools (Carlisle, Kelcey, & Berebitsky, 2013; Scott, Jamieson-Noel, & Asselin, 2003; Wright & Neuman, 2014).

1. Biemiller, A. (2001). Teaching vocabulary. American Educator, 25(1), 24-28.
2. Cantalini, M. (1987). The effects of age and gender on school readiness and school success. Unpublished doctoral dissertation. Ontario Institute for Studies in Education. Toronto, Ontario.
3. Carlisle, J. F., Kelcey, B., & Berebitsky, D. (2013). Teachers' support of students' vocabulary learning during literacy instruction in high poverty elementary schools. American Educational Research Journal, 50(6), 1360-1391.
4. Catts, H. W., Adlof, S. M., & Weismer, S. E. (2006). Language deficits in poor comprehenders: A case for the simple view of reading.
5. Hart, B., & Risley, T. R. (1995). Meaningful Differences in the Everyday Experience of Young American Children.
6. Jeon, E. H., & Yamashita, J. (2022). L2 reading comprehension and its correlates. In EH Jeon & Y. In'nami (Eds.), Understanding L2 Proficiency, 29-86.
7. Morrison, F. J., Williams, M. A., & Massetti, G. M. (1998). The contributions of IQ and schooling to academic achievement. In Annual meeting of the Society for the Scientific Study of Reading, San Diego, CA.
8. Pearson, P. D., Hiebert, E. H., & Kamil, M. L. (2007). Vocabulary assessment: What we know and what we need to learn. Reading Research Quarterly, 42(2), 282-296.
9. Scott, J. A., Jamieson-Noel, D., & Asselin, M. (2003). Vocabulary instruction throughout the day in twenty-three Canadian upper-elementary classrooms. The Elementary School Journal, 103(3), 269-286.
10. Stahl, S. A., & Nagy, W. E. (2007). Teaching word meanings. Routledge.
11. Stanovich, K. E. (1986). Matthew effects in reading: Some consequences of individual differences in the acquisition of literacy. Reading Research Quarterly, 21, 4.
12. Wright, T. S., & Neuman, S. B. (2014). Paucity and disparity in kindergarten oral vocabulary instruction. Journal of Literacy Research, 46(3), 330-357.

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Why We Intentionally Teach Select Vocabulary

We emphasize targeted instruction of carefully selected individual words that students are likely to encounter across English classes, academic subjects, and high-stakes exams. While students learn vocabulary both through direct instruction and incidental exposure during reading, research shows incidental learning through reading alone is limited—students typically learn only a small percentage of unknown words they encounter this way (Swanborn & de Glopper 1999). This is particularly problematic for struggling readers, who are least likely to develop vocabulary effectively through independent reading (McKeown 1985).

The National Reading Panel (2000) has identified vocabulary as one of five key aspects of literacy and has this to say about the direct vocabulary instruction:

“There is a need for direct instruction of vocabulary items that are required for a specific text to be read as part of the lesson. Direct instruction was found to be highly effective for vocabulary learning (Tomeson & Aarnoutse, 1998; White, Graves, & Slater, 1990; Dole, Sloan, & Trathen, 1995; Rinalid, Sells, & McLaughlin, 1997). In addition, the more connections that can be made to a specific word, the better it seems to be learned.”

Research strongly supports that direct vocabulary instruction significantly improves students' mastery of taught words and enhances their comprehension of texts containing those words (e.g., Stahl & Fairbanks, 1986)

In addition, reading comprehension interventions most often ignore the “what” of reading, i.e. the ideas and concepts within text. Simply put, the more readers understand the topics that they are reading, the better their comprehension (Gasparinatou & Grigoriadou, 2013). By intentionally and carefully selecting vocabulary across a large number of subjects, we aim to diversify knowledge building.

1. Gasparinatou, A., & Grigoriadou, M. (2013). Exploring the effect of background knowledge and text cohesion on learning from texts in computer science. Educational Psychology, 33(6), 645-670.
2. McKeown, M. G. (1985). The acquisition of word meaning from context by children of high and low ability. Reading Research Quarterly, 482-496.
3. National Reading Panel (US), National Institute of Child Health, & Human Development (US). (2000). Report of the National Reading Panel: Teaching children to read: An evidence-based assessment of the scientific research literature on reading and its implications for reading instruction: Reports of the subgroups. National Institute of Child Health and Human Development, National Institutes of Health.
4. Stahl, S. A., & Fairbanks, M. M. (1986). The effects of vocabulary instruction: A model-based meta-analysis. Review of Educational Research, 56(1), 72-110.
5. Swanborn, M. S., & De Glopper, K. (1999). Incidental word learning while reading: A meta-analysis. Review of Educational Research, 69(3), 261-285.

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How We Select Words

Membean is designed to support vocabulary development for students in grades 6-12 and beyond. The selection of vocabulary items is grounded in a carefully curated blend of general English words and domain-specific terminology.

Widely useful high-utility Tier 2 words (Beck et al., 2002) are selected from corpus analysis of a wide variety of books read in English classrooms. The Living Word Vocabulary (Dale & O'Rourke, 1976, Biemiller, 2004) gives estimates of words known by school-age students and we've used it to refine the number of words to a manageable subset.

We then add words that are more common in academic contexts culled from The Academic Word List (Coxhead, 2000), the newer Academic Vocabulary List (Gardner & Davies 2013) and the Oxford Phrasal Academic Lexicon.

Recognizing the motivations of many students to excel on high-stakes standardized tests (e.g., PSAT, SAT, ACT, IB), we also incorporate carefully selected Tier 3 vocabulary. These discipline-specific and complex terms are identified through analyses of published test materials and specialized corpora, such as Breland's (1994) College Board Vocabulary study.

1. Beck, I. L., McKeown, M. G., & Kucan, L. (2013). Bringing words to life: Robust vocabulary instruction. Guilford Press.
2. Biemiller, A. (2003). Vocabulary: Needed if more children are to read well. Reading Psychology, 24(3-4), 323-335.
3. Breland, H. M., Jones, R. J., Jenkins, L., Paynter, M., Pollack, J., & Fong, Y. F. (1994). The college board vocabulary study. ETS Research Report Series, 1994(1), i-51.
4. Coxhead, A. (2000). A new academic word list. TESOL Quarterly, 34(2), 213-238.
5. Dale, E., & O'Rourke, J. (1976). The living word vocabulary, the words we know: A national vocabulary inventory.
6. Gardner, D., & Davies, M. (2014). A new academic vocabulary list. Applied Linguistics, 35(3), 305-327.

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How We Align with the Science of Reading (SOR)

Research shows that knowing word meanings is crucial for reading comprehension at every stage of development (Cromley & Azevedo, 2007; Wagner & Ridgewell, 2009). When students grasp both individual word meanings and how words work together in context, they can build mental pictures of what they're reading. Even basic knowledge of unfamiliar words can dramatically improve comprehension, particularly when students understand how these words function within specific texts (Perfetti & Stafura, 2014, 2017).

Vocabulary knowledge directly impacts text readability, as demonstrated by Chall and Dale (1995), who found that the difficulty of words in a text significantly influences a reader's ability to engage with it. For students learning English as a second language (L2), achieving effective comprehension of complex texts such as novels or newspapers—commonly expected at upper school levels—requires a robust vocabulary of 8,000-9,000 word families and coverage of 98% of the vocabulary of the text (Nation 2006).

It's unsurprising therefore that the popular Reading Rope visual metaphor (Scarborough 2001) includes vocabulary knowledge as a critical strand in weaving together the comprehension process.

1. Chall, J. S. (1995). Readability revisited: The new Dale-Chall readability formula.
2. Cromley, J. G., & Azevedo, R. (2007). Testing and refining the direct and inferential mediation model of reading comprehension. Journal of Educational Psychology, 99(2), 311.
3. Nation, I. S. P. (2006). How large a vocabulary is needed for reading and listening? Canadian Modern Language Review, 63, 59—82.
4. Perfetti, C., & Stafura, J. (2014). Word knowledge in a theory of reading comprehension. Scientific Studies of Reading, 18(1), 22-37.
5. Scarborough, H. S., Neuman, S. B., & Dickinson, D. K. (2001). Connecting early language and literacy to later reading (dis) abilities: Evidence, theory, and practice. Handbook of Early Literacy Research, 1.
6. Stafura, J. Z., & Perfetti, C. A. (2017). Integrating word processing with text comprehension. Theories of Reading Development, 9-32.
7. Wagner, R. K., & Ridgewell, C. (2009). A large-scale study of specific reading comprehension disability. Perspectives on Language and Literacy, 35(5), 27.

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How We Align with the Science of Writing (SOW)

A strong vocabulary shapes powerful writing. When writers command a rich array of words, they can express ideas precisely, build complex arguments, and craft nuanced messages.

Writing, as a cognitively demanding task, places significant strain on the cognitive system, particularly on working memory (Kellogg, 2008; Kellogg & Raulerson, 2007). The dual challenge of generating ideas while managing language structures requires writers to juggle multiple processes simultaneously. Research shows that essays judged to be of higher quality consistently contain linguistic features associated with sophisticated and varied vocabulary (McNamara, Crossley & McCarthy, 2010). However, producing such language adds an additional cognitive load, making strong vocabulary knowledge even more critical. As Thierry Olive (2012) explains:

“Composing a good text requires writers to use language in a creative way, which means avoiding frequent forms of language in order to use sophisticated vocabulary and syntactic forms. Because frequent words are more prone to be prepotent, writers need to inhibit these frequent words and retrieve words with controlled searches in their mental lexicon.”

When language processes—like a ready access to vocabulary—are not automatic, cognitive resources that can be put towards planning and evaluating one's writing are overburdened (McCutchen, 1996, 2011). Therefore linguistic fluency in vocabulary is a prerequisite for good writing. Please see the section on how words are taught for additional details.

1. Crossley, S., & McNamara, D. (2010). Cohesion, coherence, and expert evaluations of writing proficiency. In Proceedings of the Annual Meeting of the Cognitive Science Society (Vol. 32, No. 32).
2. Kellogg, R. T. (2008). Training writing skills: A cognitive developmental perspective. Journal of Writing Research, 1(1), 1-26.
3. Kellogg, R. T., & Raulerson, B. A. (2007). Improving the writing skills of college students. Psychonomic Bulletin & Review, 14, 237-242.
4. McCutchen, D. (1996). A capacity theory of writing: Working memory in composition. Educational Psychology Review, 8, 299-3.
5. McCutchen, D. (2011). From novice to expert: Implications of language skills and writing-relevant knowledge for memory during the development of writing skill. Journal of Writing Research, 3(1), 51-68.
6. Olive, Thierry. "Working memory in writing." In Past, Present, and Future Contributions of Cognitive Writing Research to Cognitive Psychology, pp. 485-503. Psychology Press, 2012.

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How We Teach Nuance for Literacy

Please see the previous two sections on alignment with Science of Reading and Science of Writing.

Unfortunately, the way vocabulary is generally taught in schools is ineffective, tedious, and uninspired, often leading to temporary learning but not the ability to use the new words productively. In order to acquire the language of schools, and of particular subject areas, students need constant opportunities to see, hear and use that language. Playful encounters with words that arouse curiosity and interest in learning and using words are valuable in acquiring greater metalinguistic awareness.

There's growing consensus that effective vocabulary instruction requires three critical components: (a) breadth of information, encompassing both definitional and contextual knowledge; (b) active, deep processing of words; and (c) multiple exposures to target vocabulary (Mezynski, 1983; Stahl & Fairbanks, 1986). These elements align with theories such as the Lexical Quality Hypothesis (Perfetti & Hart, 2002), which posits that high-quality word representations—rich in nuance and detail—facilitate rapid and accurate retrieval of meaning when encountering words in context.

Despite the importance of teaching words with depth and nuance, this process is recognized as highly labor-intensive (Beck, Perfetti, & McKeown, 1982). It demands significant instructional effort to ensure students develop a comprehensive understanding of a word's meaning, usage, and associations.

We address this challenge by employing an innovative approach to vocabulary instruction through “Memlets” which provide multimodal representations of each word. Memlets encapsulate different dimensions of a word, promoting deep processing that is essential for long-term vocabulary acquisition and improved comprehension.

A sample of Memlets with details on why they were included is described below:

1. The Context Relationship Memlet is specifically designed to illustrate how a word functions within a scaffolded, everyday context. Each target word appears at least three times in a cohesive paragraph, enhanced with context clues (Graves & Slater, 2016). These guide students to infer the word's meaning before encountering its explicit definition (Jenkins, Matlock, & Slocum, 1989).
2. The Word Sums Memlet illustrates how each word is decomposed into its constituent morphemes and how these elements combine to create meaning. Additionally, every affix is connected to other related words, allowing students to understand how the root influences the meanings of various words (Bowers & Kirby, 2013).
3. The Definition Memlet presents ELL-friendly, child-friendly, and easy-to-understand full sentence definitions. In case of polysemy we prefer to teach the uncommon definition (Beck et al, 2008; Graves et al, 2012; Berry, 2000).
4. The Constellation Memlet is a network of words (Miller 1995) that allows a student to explore semantic relationships such as hyponymy, hypernymy and understand polysemy—developing a depth of knowledge of every word (Birgit, 1999).
5. The Memory Hook Memlet is a mnemonic method to develop an association between the target word and associated other words or descriptions (Raugh & Atkinson, 1975; Pressley et al 1982; Vanlee 2013).
6. The Images Memlet and Video Memlet provide visual and multimedia representations of the word. These include illustrative images and short video clips demonstrating the word in use. This dual-coding approach reduces cognitive load, engages students, and reinforces the real-world relevance of the vocabulary (Teng & Zhang, 2023; Clark & Paivio, 1991).

1. Beck, I. L., McKeown, M. G., & Kucan, L. (2008). Creating robust vocabulary: Frequently asked questions and extended examples. Guilford Press.
2. Beck, I. L., Perfetti, C. A., & McKeown, M. G. (1982). Effects of long-term vocabulary instruction on lexical access and reading comprehension. Journal of Educational Psychology, 74(4), 506.
3. Berry, Roger. “‘Youser-friendly’ metalanguage: What effect does it have on learners of English?.” (2000): 195-212.
4. Clark, James M., and Allan Paivio. "Dual coding theory and education." Educational Psychology Review, 3 (1991): 149-210.
5. Graves, M. F., & Slater, W. H. (2016). Vocabulary instruction in the content areas. In Content Area Reading and Learning (pp. 437-460). Routledge.
6. Graves, M. F., August, D., & Mancilla-Martinez, J. (2012). Teaching vocabulary to English language learners. Teachers College Press.
7. Henriksen, Birgit. "Three dimensions of vocabulary development." Studies in Second Language Acquisition, 21(2) (1999): 303-317.
8. Kirby, J. R., & Bowers, P. N. (2017). Morphological instruction and literacy. In Theories of Reading Development, 15, 437.
9. Mezynski, K. (1983). Issues concerning the acquisition of knowledge: Effects of vocabulary training on reading comprehension. Review of Educational Research, 53(2), 253-279.
10. Miller, G. A. (1995). WordNet: a lexical database for English. Communications of the ACM, 38(11), 39-41.
11. Perfetti, C. A., & Hart, L. (2002). The lexical quality hypothesis. In Precursors of Functional Literacy, 11, 67-86.
12. Pressley, M., Levin, J. R., & Delaney, H. D. (1982). The mnemonic keyword method. Review of Educational Research, 52(1), 61-91.
13. Raugh, M. R., & Atkinson, R. C. (1975). A mnemonic method for learning a second-language vocabulary. Journal of Educational Psychology, 67(1), 1.
14. Siriganjanavong, V. (2013). The mnemonic keyword method: Effects on the vocabulary acquisition and retention. English Language Teaching, 6(10), 1-10.
15. Stahl, S. A., & Fairbanks, M. M. (1986). The effects of vocabulary instruction: A model-based meta-analysis. Review of Educational Research, 56(1), 72-110.
16. Teng, M. F. (2023). The effectiveness of multimedia input on vocabulary learning and retention. Innovation in Language Learning and Teaching, 17(3), 738-754.

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How We Build Access Fluency for Literacy via Smart Reinforcement

For both reading comprehension and writing it's important to develop fluency in vocabulary access since if a word's meaning is challenging to retrieve, the reader is forced to devote attentional resources that are needed for comprehension or writing planning (Mezynski, 1983).

However, this access is easily eroded with time and prone to rapid forgetting unless it is consistently reinforced, requiring multiple opportunities to engage with each word (Webb, 2007). The single most important intervention in learning is the opportunity to learn what we need to know multiple times.

We address this challenge through a systematic approach that ensures long-term retention. Words are reintroduced repeatedly, even long after their initial encounter, to strengthen memory and prevent forgetting. The program employs nuanced, progressively challenging questions that begin with recognition tasks and advance to pure recall exercises. These include a variety of formats such as multiple-choice, cloze, open cloze, visual identification, and multiple variants of Select All That Apply (SATA) questions. This diversity ensures that words are encountered in multiple contexts, enabling robust encoding while also allowing learners to correct misunderstandings.

Over time, this method results in durable memory traces and effortless access to word meanings when needed, supporting both comprehension and expressive tasks (Dempster, 1987; Pavlik & Anderson, 2005, Pavlike 2007). By combining repetition with increasingly sophisticated retrieval tasks, we foster a deep and accessible vocabulary foundation.

1. Dempster, F. N. (1987). Effects of variable encoding and spaced presentations on vocabulary learning. Journal of Educational Psychology, 79(2), 162.
2. Mezynski, K. (1983). Issues concerning the acquisition of knowledge: Effects of vocabulary training on reading comprehension. Review of Educational Research, 53(2), 253-279.
3. Pavlik, P. I. (2007). Understanding and applying the dynamics of test practice and study practice. Instructional Science, 35, 407-441.
4. Pavlik Jr, P. I., & Anderson, J. R. (2005). Practice and forgetting effects on vocabulary memory: An activation–based model of the spacing effect. Cognitive Science, 29(4), 559-586.
5. Webb, S. (2007). The effects of repetition on vocabulary knowledge. Applied Linguistics, 28(1), 46-65.

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Why We Ask Many Questions

Students generally dislike being tested and when left to their own devices don't use self-quizzing as a learning strategy. Membean on the other hand spends almost 80% of instruction time asking questions.

It's long been known that retrieving what you learn in the form of questions promotes learning of complex material (Carpenter 2012; Karpicke 2012). Students who practice with questions have a dual advantage over those who don't since they have a more accurate sense of what they do and don't know and in addition obtain the benefits of the Testing Effect (Roediger & Karpicke 2006). There's also preliminary evidence that learning from questions is more effective than elaborative time-intensive methods such as concept mapping (Karpicke & Blunt, 2011).

By continually engaging in active retrieval by asking many interesting questions—a technique often referred to as “test enhanced learning with feedback,” we ensure that what's learned stays learned.

1. Carpenter, S. K. (2012). Testing enhances the transfer of learning. Current Directions in Psychological Science, 21(5), 279-283.
2. Karpicke, J. D. (2012). Retrieval-based learning: Active retrieval promotes meaningful learning. Current Directions in Psychological Science, 21(3), 157-163.
3. Karpicke, J. D., & Blunt, J. R. (2011). Retrieval practice produces more learning than elaborative studying with concept mapping. Science, 331(6018), 772-775.
4. Roediger III, H. L., & Karpicke, J. D. (2006). Test-enhanced learning: Taking memory tests improves long-term retention. Psychological Science, 17(3), 249-255.

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How We Engage in Differentiation

Differentiation, when implemented effectively—whether through intentional design or interactional strategies—can yield significant benefits in a literary classroom (Puzio et al., 2020). However, achieving this level of effectiveness poses considerable challenges. Over 80% of teachers report difficulties in implementing differentiation, particularly in today's increasingly diverse classrooms, where tailoring instruction requires substantial effort and resources.

We address these challenges by facilitating personalized learning through an adaptive approach. The process begins with a quick initial calibration (Meara, 1987; Mochida & Harrington, 2003) to estimate each student's receptive vocabulary level. Based on this data, we provide tailored word lists and content for students at different levels of proficiency.

To ensure students remain in their optimal “Goldilocks Zone” for learning—neither overwhelmed nor under–challenged—we utilize our extensive question bank to deliver appropriately leveled practice. This structured yet flexible approach makes differentiation not only manageable for educators but also highly effective for students, promoting individualized growth in vocabulary and comprehension.

With the understanding that “fair isn't always equal,” each student receives personalized assessments and generative writing assignments tailored to their unique learning needs and levels. These assignments are designed to prepare students for the practical application of vocabulary in everyday communication. This individualized engagement promotes deeper cognitive processing, which research shows is essential for enhancing memory retention (Zhou, 2024). By integrating personalization into both assessment and application, students are not only equipped with vocabulary knowledge but also the skills to use it effectively in real-world contexts.

1. Meara, P., & Buxton, B. (1987). An alternative to multiple choice vocabulary tests. Language Testing, 4(2), 142-154.
2. Mochida, K., & Harrington, M. (2006). The Yes/No test as a measure of receptive vocabulary knowledge. Language Testing, 23(1), 73-98.
3. Puzio, K., Colby, G. T., & Algeo-Nichols, D. (2020). Differentiated literacy instruction: Boondoggle or best practice? Review of Educational Research, 90(4), 459-498.
4. Zhou, K., Jin, F., Li, W., Song, Z., Huang, X., & Lin, C. H. (2024). The design of technology-enhanced vocabulary learning: A systematic review. Education and Information Technologies, 1-23.

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Final Thoughts

Classrooms today are more diverse than ever, yet there is no single vocabulary tool that effectively supports the full spectrum of learners—from those building foundational skills, to multilingual learners, to those seeking advanced challenges. Schools often resort to investing in separate tools for different groups, resulting in a fragmented and inefficient approach to vocabulary instruction.

Many existing solutions focus narrowly on teaching individual words, overlooking the broader and more critical goal of fostering word consciousness (Scott et al., 2008). Word consciousness refers to a learner's awareness and curiosity about language, enabling them to independently acquire new words. Developing this skill requires rich, contextualized content that provides depth and nuance for each word—an aspect that is often overlooked due to the complexity of creating such resources.

Additionally, most vocabulary interventions emphasize the volume of learning achieved without considering the efficiency of the learning process. In supplemental programs, where instructional time is often limited, efficiency is paramount. Every minute of classroom time is precious, and tools must deliver maximum learning impact within these constraints.

To bridge these gaps, vocabulary instruction must adopt a unified, comprehensive approach that supports diverse learners, builds word consciousness, and prioritizes efficient use of instructional time through rich, contextualized content and adaptive learning strategies.

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