About Lexile WordBank
Repeated encounters with words in meaningful contexts provide the best opportunity for successful vocabulary development. As a result, curriculum and assessment developers need up-to-date information about the words students are likely to encounter in their school reading to focus attention on the words students will actually encounter.
- Which words are students likely to encounter at different levels and in different domains?
- Which words are students likely to know or not know at different levels?
- Which words have the most value for direct instruction?
The Lexile WordBank is a vocabulary resource containing 40,000 unique words from the Landscape of American Schools English Corpus created from the top four best-selling textbook programs, all published after 2011, in science, math, social studies, and reading/English language arts (ELA). WordBank provides content, curriculum, and assessment developers with rich information about the words students will likely encounter in their school reading. Data from WordBank can be integrated into existing development systems, where filtering and sorting features can be used to identify the specific words best suited to a particular purpose.
Lexile Measures
WordBank includes Lexile word measures for approximately 25k words. These Lexile word measures estimate the challenge a particular word presents to a particular reader during independent reading. Lexile word measures were developed with over 7 million reading-comprehension item responses and patterns of word use in MetaMetrics' 1.4-billion-word corpus of K-12 reading materials.
Lexile word measures range from BR to 1825L and can be interpreted in the context of how challenging the words are relative to the text in which they appear. For example, if an 800L reader is reading an 800L text, she would be expected to correctly answer reading comprehension questions concerning the text 75% of the time. When she encounters a word that is at 800L, then we would expect her to have a good understanding of the word and independently be able to use the word in context.
If the same reader encounters a 1050L word in the same 800L text, we would expect her to understand the background concepts associated with the word, but not have a complete understanding of the word or be able to use the word independently in context (50% understanding). In other words, she is "ready" to learn the word.
Similarly, if the same reader encounters a 650L word in the same 800L text, we would expect her to completely understand the word and be able to use the word in context with ease (90% understanding).
Data Manipulation
As the Lexile WordBank is delivered as a Microsoft Excel spreadsheet (XLSX), it is expected that licensees will have a working knowledge of how to access and manipulate the data using basic spreadsheet features like sorting, filtering, and merging (for situations where WordBank data is being added to an existing development system).
Word Frequency Interpretation
Because the Lexile WordBank is based on multiple textbook programs in each grade and domain, the total number of occurrences of a word (frequency) can be interpreted as the expected number of times a student would encounter a word in their school materials. However, textbook materials are an important source of word exposure for students, but they are not the only ones. Over future releases, the Lexile WordBank will reference additional materials like trade books, online content, and more. The reported frequency measures will remain interpretable as the expected number of encounters for students from grades 1 to 12.