I would not have thought one typo would lead to such criticism of my form, as they appear quite frequently in many of the responses here. My wife is a teacher so I have a bit different perspective.
It's not about pointing out typos so much as pointing out
irony. If you're going to talk about the merits of education in a post with typos, people are bound to chuckle. Like when Roger Ebert complains about a script, knowing he has "Beyond the Valley of the Dolls" on his resume. I've done it, too, you just have to suck it up.
As I said, my wife is a teacher, too. When we have kids, we won't take them out of school as long as she's teaching because her work ethic (and her school system) would never allow it. But if she ever switched careers or retired, I'm not sure she'd ever be as cool about taking kids out of school, either.
As far as your original post about compensating teachers for all that extra time, this might seem O/T, but I'd suspect most people on the forum have been known to do something outside their job description, for no extra pay, if the situation required it. Sometimes, my job requires I work extra-long hours in order to get a certain project done on time. And it's not (necessarily) laziness on my part. Last Friday, I was given an assignment at 10:30 am that had to be done before I left, but it also required the participation of other people (sorry, trying to keep what I do for a living vague), and I had to wait until they were available before we could all work on the project. I didn't get home until 10pm that night. But it's what happens sometimes. Didn't expect the assignment, didn't necessarily want it, but it had to be done and fell to me and a few other people to do it. And every single person on here probably has a similar story. To me, that sort of overtime is only unforgiveable when the employee is paid hourly and does not get compensated for that extra time. Otherwise, it's part of the job, even if it's not on the job description. And it happens to teachers, too. If it's not a packet of homework for a student's trip to Disney World, it might be a packet of homework because a child is visiting dying relatives in Altoona, or Mommy's drying out in detox and the kid has to spend a week or two with their grandpa who lives in another district. Or it might be a trip sanctioned by another department in the school (Band's going to Disney World, but the math teacher is planning an algebra test the day after they return). Or the kid is falling behind and desperately wants to catch up.
What's important is that hopefully the student and the student's parents recognize that a trip isn't a "Get out of homework free" card. That being a student should be treated like a job, and whatever your job is, you're always supposed to strive to do it well. My wife gets a little angry (and a little jealous) when students or parents tell her about vacation plans 2 or 3 days before they happen (or even less). But a student with parents who genuinely give a crap as to how their kid is doing, who let teachers know months ahead of time what the plan is and genuinely want to help out? Most teachers are thrilled when parents are that interested & involved.