Being a guitar teacher myself I understand the value of a great teaching resource. YouTube is one of the more useful tools for teachers and students across the world today, with access to lessons on just about everything. This is good when you know what you're looking for, but it doesn't put into place a step by step lesson structure.
Guitar Tutor Online offers such a tool for guitar teachers both starting and experienced. With over 150 lessons, if you and your students could do 3 lessons per week, then that is one years worth of lesson plans available in one site. If you are a teacher and find this site one you frequently visit during guitar lessons then please give this site the credit it deserves buy suggesting to your students that they subscribe.