Lexile levels are measures of both a reader’s ability level and a text’s difficulty. They are based on a scale that rates reading scores and reading materials from a beginning first grade level to an adult workplace reading level. Lexiles were developed by MetaMetrics©, funded initially by the National Institute for Child Health and Human Development (popularly called NICHD).
Let’s look at Lexile levels for readers. The range of Lexiles is 5L (Beginning Reader) to 2000L, with intervals of five. A higher reading Lexile level is associated with a higher reading level. Typically, a range of Lexile scores are associated with each grade level from second grade on. These Lexile scores are derived from a wide range of popular reading assessments, including DIBELS, Aimsweb, Performance Series, Iowa Tests, and multiple state reading assessments.
Similarly, Lexile levels are used to report text difficulty. Lexile text measures are based upon word frequency (vocabulary) and sentence length (syntactic complexity). MetaMetrics© analyzes texts by computer and assigns a Lexile in increments of ten. The goal is to match student and text Lexile measures as a starting point for determining appropriate reading materials. The Lexile measures also provide teachers and parents a sense of whether textbooks and classroom materials fall within a reasonable range of student abilities.
There are other factors besides Lexile levels to consider when matching students to reading materials. Student interest and knowledge affect readability for students. One of my kiddos is an avid reader of a series which is well above his measured reading level. His comprehension often falters as he reads (although the graphic features provide additional support). Regardless, he LOVES the zany characters and devotes considerable effort as he reads for pleasure.
The graphic above is provided by MetaMetrics© for sharing with “students and peers,” so I assume my readers fall into one of those categories. Here is a link to the entire document and the website is definitely worth checking out: Infographic8.5x11_updated