Fluency is directly linked to comprehension. Student fluency is a good indication of their comprehension or understanding of the text they are reading. Fluent reading (smooth, at a nice pace with lots of intonation and attention to punctuation ) indicates that the student is making sense of the text as they are reading. Poor fluency often means that a text is too difficult. Students working in a text too difficult will lose meaning while working on decoding the words they are reading-more effort being used to solve words affecting how well the student can read for meaning.
This sight has some nice activities to promote fluency with your classes
Printable Scripts for Reader's Theatre