Fear and Loathing in Middle School

Things I'm sick of hearing from my students...
"I couldn't do it because it was too hard."
"I couldn't do it because my printer/computer/mouse/keyboard/disk/etc... was broken."
"I couldn't do it because it didn't make sense."
"I couldn't do it because I left my book at school."
"I couldn't do it because I don't understand Latin."
"I couldn't do it because I was on vacation."
"What was I doing?"
"What's wrong with saying...?"
"Mr. Lind, whoa, there was this one time, when, seriously, this will just take 15 seconds, so like this one time..."
"I was just playing."
But, really, God love 'em all. There's no birth control like teaching. I do honestly enjoy what I do, but sometimes, just sometimes, I wish I could say, "Move a little to the left," and press a button in my classroom that would open up a trapdoor to the bottomless abyss, like Montgomery Burns has.
But most of the time, my job is rapturous bliss. I saw this teacher on a PBS show while I was home during the snow day. He was talking about how rewarding and wonderful teaching is and how all of his students were so precious. I would say that 90% of my students are blessings to me everyday. However, I would say that the other 90% have given me cause for frustration everyday as well.
How can someone honestly talk about how wonderful other humans are? Did they suddenly fall through several dimensions into the Twilight Zone? People are by nature selfish, rude, arrogant, opinionated, and misinformed, and I myself fall very hard into all of these categories. As a Christian, I believe it is a privilege to serve others and live selflessly. However, I and all my fellow human beings fail at this daily. Then think about children, who have not yet internalized what it means to be selfless, and who simply need more attention and concern than adults. Realize that I spend my day working with these folks.
The sad part is, though, as we get older, we get more self-righteous. Most kids I have dealt with don't really believe that they are more important, more intelligent, or more correct than most adults. However, we grown-ups can be obsessed with the battle over who has a monopoly on truth, justice, and intelligence.