I'm always on the lookout for new edtech tools to improve student reading skills. Check out my Wakelet collection with Online Reading Tools

This year I decided to use ReadTheory with my students. What I like about this tool is that it personalizes reading for each student. The tool automatically recognizes the student's reading level and matches it with the appropriate text and questions. The teacher does not assign reading texts, the tool does. After students take a placement pretest, they are placed at a level and are assigned reading passages at random from within that level for the student. Students are continually challenged to improve their reading skills and move to the next reading level. Text complexity is measured with the Lexile Framework for Reading. Students can also earn knowledge points, e.g. 1 KP per question, 2 KP for a challenge question, 30 KP for getting a perfect score on a quiz, etc. KPs are solely motivational in nature and can be used to facilitate in-class competitions. 

So as a teacher I don't have to spend my valuable time on trying to find appropriate reading passages for each of my students nor on grading. Isn't that awesome? All the questions are graded automatically and a detailed explanation is given to students for each wrong answer. Along with multiple choice questions, teachers can add one written response question per quiz (carefully crafted by the ReadTheory Team) so that students can write freely formed compositions which are then graded by the teacher. An assessment rubric is provided for this type of question.  

Teachers can easily measure student progress based on their lexile level, grade level or knowledge points and quizzes taken.

What's more, ReadTheory offers printable reading assessments updated on a monthly basis.

And last but not least, ReadTheory is completely free of charge for an unlimited number of students per school. 
Thank you ReadTheory Team, your work is greatly appreciated.