Guest speaker at a high school graduation

Phone call from Jojo. Am a bit surprised that I'm being invited as "guest speaker" at the school's HS commencement tomorrow. Actually, I don't feel like a "guest" there. I see and share with the high school kids during our weekly Thursday bible studies. I was there during their retreats, camps, and even in their classrooms teaching some subjects! Ok. I'll be their guest speaker who is no longer a guest!