Notes on a graduation note under the door

The small envelope had been slipped under the door of my office when I walked in today. It was addressed to "Dr. Clark." I opened it, to find a note from a graduating student.
Saturday, I'll attend another UCO graduation, watching students march across the stage and have their names read, while parents and families and friends yell and clap. The students will smile, pose for photos, and walk briskly off stage, some holding their diploma covers high. All will be smiling. 

Out of the hundreds in that room, I will know about 50, like the note writer, as former students in my classes over the past four or five years. Most of them I know by name, and for a large portion, I know their personal stories and trials, and their hopes and plans for the future. 
Yes, I'll be wearing my "funny hat," and academic regalia, and the faculty will march in to the gym to "Pomp and circumstance," down the aisle between the already seated students. We'll take our chairs in front of them, and then, after the national anthem and a few introductions and short speeches, they'll file past. Many will catch my eye, and smile. I clap for my students when they do get their degrees, giving thumbs up when they see me.
After graduation, they'll gather out on the lawn, meeting family and friends, and a few will want their photos taken, and I'll meet parents, family, finances or spouses for a few. Then it will be over, but it's not, because many will stay in touch, some becoming friends. A few will graduate to calling me "Terry," while others, even decades later, still call me   "Dr. Clark." 
I get a few cards and presents every year from appreciative students. I don't think they know how much I appreciate them though.  I treasure the time with these students, their energy, their hopes, their futures,  and I'm enriched by the time I spend with them, helping them on their way. 
That's why teaching keeps you young,  even though their youth reminds you how old you are. 
To be a good teacher you have to like students, to see their potential, to allow their individuality, to not give up on them, and to be a demanding encourager. And when you succeed, the rewards are unexpected and treasures, like notes slipped under the door.