During reading instruction, for example, the teacher will move between direct and guided instruction based on the progress of the students and the difficulty of the text or concepts presented. Direct instruction is an instructional approach where you explicitly teach students learning strategies by modeling and explaining why, when, and how to use them. Guided instruction provides students with opportunities to practice under your guidance. It requires extensive interaction between you and your students. The teacher's principal role is that of coach.
The move from direct instruction to the next phase, guided practice, depends upon how well you think the majority of your students have internalized the use of the particular strategy and understand the material presented. As with most areas of learning, all students do not learn the same material at the same rate and with the same understanding. If you move too quickly from one phase to another, some students will become confused or frustrated. If you move too slowly, others may become bored or lose interest. So how do you know when to make the shift? By engaging in ongoing informal assessment through monitoring your students' learning. From such a simple assessment, you may decide that many students are ready for the guided practice phase or that others may need additional direct instruction.
Adapted from Strategic Teaching and Reading Project Guidebook. (NCREL, 1995, rev. ed.).