I saw a meme the other day and, despite a 15-minute Google search, I cannot find it now.
What it said was this:
“Teachers are not on summer break. They are in recovery.”
Truer words were never spoken.
I recognize other stressful professions don’t get nine weeks every year to recover. I am grateful for people who do those jobs. That doesn’t change the fact that teaching is an emotional roller-coaster. Through the year, I invest so much of myself in my students, my curriculum, and my fellow teachers that the experience leaves me feeling paper thin. As I age, my skills in the classroom continue to evolve and develop, but my stamina decreases with every year. I enter each summer break more tired and worn than the previous. 
I had a fabulous year this year. At the beginning of the school year, I moved into my brand-new classroom. I had a wonderful group of students who reached and then surpassed every expectation I set. My department worked together as a team, trying new things and collaborating to do what is best for students. The parents were so helpful and supportive. So many amazing things happened this year, and yet I am emotionally, mentally, and physically exhausted. I watched new hires go through what every new teacher experiences and reminded myself that this job is really difficult. Those of us who have been here for a while forget just how challenging teaching can be because we have learned to navigate the waters so well. Still, it takes a toll.
I (and I imagine most of my fellow teachers) will have a summer filled with planning new curriculum, selecting new concert repertoire, and teaching summer workshops and camps. Despite that, being able to step away from my normal routine will help me regain a fresh focus for another school year. I can only speak for myself, but I doubt I could keep doing this job if there wasn’t an opportunity to step away and regroup.
I am certainly open to exploring other forms of school years, like trimesters or quarterly sessions, but those sorts of mountains are hard to move. Until changes happen, I will relish the opportunity to rest, re-establish my intentions, and start the next school year with a clear head.