I have found a great fluency app that helps calculate and keep track of students' fluency scores! There are six original and leveled passages for each grade level (1st-8th). Just select your student, select the passage and print it out, and start the timer when they start reading. While the student is reading you mark when they make a mistake with the push of a button and when they are done the app calculates their fluency score for you! It also saves all the assessments  you've given to students in the past for easy tracking of progress!