The Accelerated Reader program is a software-based assessment test given in elementary and intermediate schools to monitor the reading progress of studies. Accelerated Reader (AR) scores are given to each book based upon its difficulty to read. A quiz is then taken by the student with points awarded based on their understanding of the book. These points are used to monitor how the student is progressing.
Flesch-Kincaid Readability Index
Accelerated Reader scores are based first upon the Flesch-Kincaid readability index. This is a long-used method for rating the suggested age/grade level for books. The Flesch-Kincaid grade level readability formula uses average words per sentence (number of words divided by number of sentences) and average syllables per word (number of syllables divided by number of words) to calculate grade level of that material. The formula looks like this: (0.39 x average words per sentence) + (11.8 x average syllables per word) - 15.59 = reading level.
Length of the Book
Scores in Accelerated Reader also consider the length of the book, as books which take longer to read are worth more points then shorter books. It's also believed that as a reader advances they are more likely to be able to handle longer works. In the Accelerated Reader formula the number of words in the book is divided by 100,000.
The exact formula for scoring an Accelerated Reader book is to multiply the reading level plus 10 with the number of words divided by 100,000, i.e.: (10 + Flesch-Kincaid reading level) x (number of words / 100,000) = Accelerated Reader score.
For example: for a book with a Flesch-Kincaid reading level of fifth grade and 40,000 words is calculated (10 + 5) x (40,000 / 100,000) = (15) x (0.4) = 6. The book is worth 6 Accelerated Reader points.
The student is then given a quiz specifically tuned to that book. Quizzes have either five, 10 or 20 questions, depending on the reading level of that book. The quiz is checked through the computer program and the number of points awarded for that book correspond to the percent the student got right. For a book worth six AR points the student gets 6 points for a quiz score of 100 percent, 5.4 points for 90 percent, 4.8 points for 80 percent and so forth. The student must score over 60 percent on the test in order to receive credit. The software designer recommends a score of at least 85 percent as optimal for that material.