As an elementary literacy coach / RTI coach / literacy specialist / do anything on campus person,....... I believe that I have heard GUIDED READING defined about 10 different ways.
According to Fountas and Pinnell, guided reading is a academic approach that is designed to help individual readers build an effective system for processing a variety of increasingly challenging texts over a period of time.
To put guided reading into practice with fidelity, it is important to first assess our students and observe their reading behaviors before we begin. Through this observation and assessment, teachers should determine the independent reading level of each of their students. Once the teacher find the student's independent reading level, they should actually work with the student at least one level above their independent level - hence the instructional level. The educator will need to look at the assessment data and group students together. These groups are actually temporary / flexible and the students are alike enough in their development of a reading process that it makes sense to teach them together in a group until one or more of the students are ready to move on to a different group.
There are many important aspects to consider before selecting the text for the guided reading group. Things for the teacher to consider when selecting appropriate text: individual student strengths and needs, background knowledge of the group, reading level, language of the text, student engagement, and the potential for student growth.
The text will then be used to assist the children with expanding and growing what they know how to do as good readers.