Today I worked in the front of the classroom for 47 minutes of direct instruction, with four separate class sections. I wasn't even standing the whole time: I sat in my rolling chair for most of the period. I did even talk for the entire period: I was facilitating a class discussion, while clicking through a slideshow of prompts. And I did not even have the full class involved in this activity: this was a hybrid Socratic Seminar, so I was only really working with 10 or 11 students at a time.
This. Was. Exhausting. I'm sure that is partly because I am out of practice. But still, holy crap how do 80-something percent of teachers do this every day? I was going to continue this activity tomorrow, but nope I just can't even with this.
Currently: Having a drink at 4:15PM, typing a quick blog, then polishing off a document-based activity to consume most of tomorrow's class period while I conference with students in 2s and 3s about their discussion performance. I cannot do this again tomorrow.