Hiebert explains that:
"...the Lexiles have been recalibrated from longstanding recommendations of Lexiles for particular grade levels to a "grade-by-grade" 'staircase' from beginning reading to the college and career readiness level." (CSS Initiative, 2010, p. 8). Beginning with the grade 2-3 band text complexity levels have been increased to ensure that readers will acquire text levels of college and career by the end of high school. The explicit parameters for Lexiles by grade bands, the ease of obtaining Lexile scores, and the lack of ready access to validated qualitative rubrics mean that policymakers and educators could place considerable weight on Lexiles in choosing texts for instruction and assessment" (33).
Here is a copy of the chart of recalibrated lexile ranges from Hiebert's article:
If we are trying to "ensure" that students reach a certain reading level, though, would ask--what happens to the students who are left behind? I know there are plenty of students at my school who do not measure up to these ideals. What are we to do for them?
Hiebert takes issue with the way lexiles are measured in the first place. She argues:
"In narrative texts with substantial amounts of dialogue, average sentence length can be influenced by the author's awareness that people typically use relatively short sentences in conversations. As a result, the difficulty of narrative text is typically underestimated. Such underestimations are most evident in texts such as the classic Old Man and the Sea (Hemingway, 1952) that has a exile of 940 (which falls into the grade 4-5 band of the recalibrated Lexile levels)" (34).
This is an excellent point. No educator would give fifth graders Old Man and the Sea as an exemplar text. As an English teacher, I taught this novel to a talented group of freshmen, many of whom still struggled with the novel's larger concepts. Clearly, lexile measures cannot stand alone.
Hiebert goes on to examine MetaMetrics' methods for examining text complexity. Through using charts, exemplars, and detailed analysis, Hiebert convincingly argues that MetaMetrics' methods are flawed. Hiebert concludes that teachers must rely on their own skills and "in-depth knowledge that comes from their experience with students and books" (39) rather than the Lexile system to match students with appropriate reading materials.
Hiebert sums up by writing:
"The important fact to remember is that a readability formula can only provide a rough estimate of a text's difficulty. Quantitative data must be followed by qualitative analyses that examine the complexity of themes and style, and texts should be considered relative to the strengths and needs of the students who will be reading them and to the contexts in which they will be used" (40).
Hiebert, Elfrieda H. "Beyond Single Readability Measure: Using Multiple Sources of Information in Establishing Text Complexity." Journal of Education. 2010/2011, Vol. 191 Issue 2, p 33-42.