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Understanding Lexile Scores

Understanding Lexile Scores


At St. Pius X Catholic School, we have a useful tool in our reading instruction toolbox called the SRI (Scholastic Reading Inventory). Administered three times a year, in August, December, and April, this brief computer-based assessment gives us a snapshot of a students’ reading level at a moment in time. This snapshot takes the form of an approximate Lexile score for the student.

When a student takes an SRI assessment, they are asked to read short passages and answer multiple-choice comprehension questions. There is no set number of questions; the test varies its difficulty automatically after each right or wrong answer, stopping the student when they have reached a level where they are consistently answering incorrectly. By administering the SRI three times a year, we get a nice picture of a student’s reading growth through the year. SRI also allows us to identify students on a reading plateau and adjust instruction accordingly. It is important to remember that each SRI is just a snapshot of reading on a given day and not the full picture of a student’s ability. The child may not feel well, they may be rushing through the test, they might have trouble concentrating — there are many reasons that a student might get an unexpected result. This is why SRI is a part of our reading curriculum, not the sum total.

Lexile is a good starting point in book selection. MetaMetrix, the company behind the Lexile, evaluates books for word frequency and sentence strength. In other words, a book’s Lexile number represents the difficulty of the words in the book. Lexile does not address the difficulty of the subject matter or the complexity of plot, characterization, or literary devices in a book. For that reason, The Great Gatsby has a Lexile of 1070 while Diary of a Wimpy Kid: Hard Luck has a Lexile of 1020. No one would equate these very different texts, but there they are, close together on the Lexile scale.

A good rule of thumb when using Lexile for book selection is to allow the student to read 50 points above their score, but up to 100 points below their score. This has been identified as the reading comprehension “sweet spot” ( So, if a student has a Lexile measurement of 500, their range of reading growth is 400- 550.

Rather than lock a student into only reading books exactly at their Lexile level, it is very important to foster a love of reading and encourage the joy of reading for pleasure. A child who loves to read will naturally seek out more challenging texts as they become a better reader. Encouraging a student to read for enjoyment is critical as they become Tweens and Teens — an age when the solitary nature of reading discourages it as a “cool” pastime. Lexile helps this age group by giving them a range to aim for when finding books to read.

If you ever have any questions on Lexile or book selection, please feel free to email Mrs. Christensen or Mrs. Parker. We are so grateful for our involved and caring parents. Thank you!