A Lexile reading measure tells a student's reading level and gives the teacher or parent an easy way to match a student with the correct text. Lexile measures have a wide range, from below 0L to 1600L. Measures that fall below 0L start with a BR, which means beginning reader.
Both students and texts are given Lexile scores. The student's Lexile measure is then matched to the text's Lexile score to ensure that the student is reading a text that is neither too easy nor too hard for her comprehension and reading skills. When a Lexile score is above 0L, a higher score means a higher reading level. When a Lexile score is below 0L, a higher score means a lower reading level. So, a student with a 500L reads at a more advanced level than a student with a 100L, but a student with a BR50L reads at a higher level than a student with a BR150L.
Many states test students' Lexile measures during required state assessments. This allows teachers an easy way to use Lexile measures the classroom as a whole, as well as comparing individual scores against Lexile averages for a certain age group. This helps the teacher determine which students are behind in reading and use that information to target students who need extra help.