Nesi draws an important line between quantitative and qualitative measures of text. She writes:
"First, quantitative measures of text complexity (such as Lexile levels and other readability formulas), while profoundly comforting and easiest to determine, can be largely misleading--if only because our over-dependence on them blinds us to the more subtle qualitative measures. Quantitative measures encourage us to slap a number, letter, or grade level on a text and be done with it. Librarians and classroom teachers know intuitively that these labels do not work--hence our sensible resistance to 'leveling' our libraries" (20).
If we are blindly adhering to the Lexile system (or any other leveling system) without considering the merits of each book individually, we are depriving students of rich reading experiences.
Nesi goes on to make an important point that other authors have neglected: the connection between readers and task. She writes:
"Depending on the ability of our students and what we ask them to do with a text, its complexity can vacillate wildly. For example, a text with a low Lexile can easily become more complex if a student's prior knowledge of the topic is limited. That very same material becomes even more complex the more critically we ask a student to think about it. It is one thing to ask a child to read an article written at a Lexile level of 1000 just to comprehend it. It is rather a different task to expect that same student to read the article to draw a conclusion from it and support that conclusion with evidence from the reading. The task, in this case, has just made the text more complex" (20).
Nesi's argument is important to note when helping students select materials. Students do not need to be held to a strict Lexile band; it is far more important to cater to student interests and allow them to be challenged by content. Teachers can develop challenging assignments to work with virtually any text; the most important job is to capture the students' interest in reading.
Nesi, Olga M. "The Question of Text Complexity: Reader and task trump traditional measures." School Library Journal. Oct. 2012, Vol. 58 Issue 10, p 20.