Closing the achievement gap is a complex problem that concerns every educator. There is so much information out there that it's hard to decide where to even start.

Here’s a recommendation that may surprise you: Start with vocabulary.

Why start there? Because a weak vocabulary undermines the foundational literacy skills you're trying so hard to build. Think about where students need to apply word knowledge: reading, writing, listening, speaking — even thinking. That's why vocabulary acquisition is so essential for success in school and beyond.

While this may seem self-evident, there is a growing body of research that conclusively validates the importance of vocabulary acquisition and its impact on literacy.

And here's the good news: implementing effective vocabulary instruction does not have to mean adopting new curriculum, or magically coming up with more teaching time. makes it easy for educators to implement systematic vocabulary instruction so that their students can start closing the gap.

But before we get to how we can help, we want to share the most important findings from the best research on vocabulary instruction. The following presents compelling evidence on the importance of vocabulary knowledge and systematic vocabulary instruction. was designed with this research in mind. So, after you've perused the research, we invite you to read on about how we can help. After all, we're in this together.

The research confirms what educators intuitively know.
Here's a statement that may seem fairly obvious to any educator: Vocabulary acquisition is essential for success in school and beyond. What's common sense to teachers is also validated by a body of research that substantiates the importance of vocabulary acquisition and its impact on literacy.

After you've perused the research, we invite you to read on about how can help. We're in this together.

The Text Complexity-Vocabulary Connection
In 2008, when researchers were looking at the curriculum used throughout the United States, they found something alarming. When they analyzed the difficulty of the reading that students were required to do in high school, they found it to be substantially less complex than the reading that would be required of these students in career training or higher education. In addition, they found that recent graduates were expected to understand these complex texts without the scaffolding that is often provided in high school: no summaries, no glossaries, no teacher's explanations.

Source: Massengill, College and Career Readiness: Through the Lens of Lexiles

This chart shows the approximate difficulty of textbooks used by high school juniors and the texts that these students are expected to read upon graduation in college and career training. The texts associated with entry-level positions and basic civic engagement are far more difficult than the average textbooks that students would have read as part of their high school education. And while college and career success depends on independent reading skills, only 13% of adults today read prose texts at a proficient level.

The Y-Axis of this chart is Lexile, which is a popular measure of text complexity. But what does Lexile really measure?  Well, one of the largest factors in calculating text complexity is word frequency. What is word frequency? It's a measure of how often you would expect to see a word in print.  Words that appear less frequently are colloquially known as "vocabulary words."

The Vocabulary Gap
In a 2003 study, researchers observed parent interaction with children starting at 6 to 8 months-old for one hour each month over the course of a year. The data shows a large difference in the number of words spoken in families of higher socioeconomic status compared to the number of words spoken between parents and children in families of lower socioeconomic status. Not only were there significantly more words spoken, but there was a greater variety of words spoken by the parents and the children of the higher SES families. The graph below shows the size of the vocabulary used by children from each cohort, at ages 12 through 36 months. The big take-away from this study is something you've likely experienced as an educator: Your students are entering their school years with a huge range in vocabulary size, with some already facing a distinct disadvantage.

Source: The Early Catastrophe, Hart and Risley, 2003

The Importance of Vocabulary Instruction
Given the findings presented above on reading demands and the vocabulary gap, it's no surprise that current research also points out the importance of vocabulary instruction. Consider the following findings, summarized in Common Core Appendix A: Research Supporting Key Elements of the Standards.

  • The importance of vocabulary instruction "cannot be overstated."
  • Vocabulary knowledge is "empirically connected to reading comprehension."
  • Vocabulary size is a "key factor in disparities in academic achievement."
  • Typical instruction is "neither frequent nor systematic."

The Middle and High School Years
The need for vocabulary instruction is especially acute in middle and high school. In the early years children pick up words by listening to their parents caregivers and teachers speak, but researchers found that by 4th and 5th grade, most students' vocabulary acquisition had stagnated. And unlike picking up vocabulary through oral language, which is supported by nonverbal clues, when students see words for the first time in print and rely on written context clues, they only "get" the correct meaning 5 - 15% of the time. Yet students need to understand 95% of words in a passage to understand the meaning of that passage.

Best Practices for Vocabulary Instruction
We've summarized the challenges we're facing. Now here's what the research suggests for the best approach to vocabulary instruction:
  • Provide direct instruction of vocabulary words within a specific text.
  • Repetition and multiple exposures in a variety of contexts is key.
  • The vocabulary words that students learn should be the words that they will find useful in many contexts.
  • Questioning and language engagement are the most effective techniques for teaching vocabulary.
Best Practices for English Language Learners
Another facet to providing effective vocabulary instruction is considering the unique needs of English Language Learners. What Works Clearinghouse is a federal resource that evaluates evidence-based techniques for teaching and recommends best practices based on gold-standard studies.

Here are WWC's recommendations for teaching vocabulary to English Language Learners :

  • Teach a set of academic vocabulary words intensively across several days using a variety of instructional activities.
  • Choose a brief, engaging piece of informational text with academic vocabulary.
  • Choose a small set of academic vocabulary for in-depth instruction.
  • Teach academic vocabulary in depth using multiple modalities.

There's a better way to teach vocabulary.
It's clear that there's an urgent need to prioritize effective vocabulary instruction. Here's what makes our approach different and, more importantly, better: is systematic. Our approach is based on teaching the words your students actually need to know. There are no "grade level" words, no units based on a random collection of words. We figure out the words your students don't know yet and are ready to learn, then systematically follow up over time until they master them. is adaptive. Every student gets a personal Learning Program that automatically keeps track of their trouble words and predicts the words they're ready to learn. We work with them at their own pace until they've achieved mastery, and follow up so they don't forget. We deliver differentiated instruction that focuses each learner to fill in the holes in their word knowledge. integrates with your curriculum. We make it easy to connect vocabulary instruction with what you're already teaching, so students learn words related to your curriculum. We have hundreds of thousands of ready-made vocabulary lists for thousands of commonly taught texts and topics. You can assign a Practice activity or Quiz based on any list in seconds, and it's easy to modify our resources and or make your own. is manageable and practical for teachers to implement. There's no new curriculum to adopt, and no complicated procedure to follow. Your teachers can literally get their classes started with vocabulary assignments in one prep period. With our ready-made resources, options to customize, and great features for student-directed learning, teachers have the flexibility to be as hands-on or as hands-off as they like. As long as students are using a few sessions each week, will teach them the words they need to learn. keeps students engaged. Our "gamified" approach to vocabulary instruction engages students in the learning process. Friendly competition motivates students to achieve their personal goals, to work together in teams, and to keep improving.

How Works is a platform for lifelong learning that grows with students every step of the way. We teach over 14,000 Tier II academic vocabulary words with over 190,000 questions, and have a library with more than 500,000 free vocabulary lists to support just about any text or topic. So whether it's a 5th grader preparing to read Walk Two Moons, an 8th grader learning morphology and roots, or a high school junior studying for the AP exam, has resources to meet the needs of every learner.

As students learn on, we continually compare each student's responses to the literally billions of data points to build a model of their personal word knowledge. We use that data to automatically differentiate instruction, giving each individual student the right words and the right questions at the right time. believes that mastery matters. That means that students learn words inside and out — multiple definitions, multiple forms, multiple contexts. We prepare students to understand words anywhere they encounter them.

It's time to elevate vocabulary instruction from supplemental to fundamental. Together, we can make real progress on our shared mission to close gaps and open doors.

Here's how you can put your students on the path to systematic vocabulary improvement:

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