Unavoidably and non-negotiably, I will be missing two days of school in a couple of weeks. My attendance is required at a wedding in L.A.*
In your general professional job, my understanding is that if you're out, you're out: calls go to voicemail, you set up an away email, and it all gets done when you get back. I've spent long hours and traded excellent shifts to get someone willing to cover me in my days as a server/bartender/retail grunt.
Teaching of course is different: there will be a substitute teacher in my classroom. Like most teachers I know, I have dragged my feverish, pale self to work - uphill in driving snow - to drop off lesson plans (even if emergency sub plans are already available). Through advance planning, I have managed to arrange not only a sub but a good one, who will be kind to my students and make every possible effort to get through some portion of the plans I leave. This year I also have a Resident, who knows how things work and is fully capable of getting through a day, and who is well-known to the kids in my class.
Before I rant, I should say that I have thankfully never done a substitute gig. I cannot imagine anything more difficult: different school, different kids, different grade every day for low pay and rotten benefits. You may or may not be left plans that make sense. You may or may not be left name tags, and you will be blamed for anything that goes wrong. YUCK. Even the very best teacher is going to be challenged by these requirements.
That said, SFUSD seems to have more than its share of sub problems. First there's the issue of availability. No matter how big the sub pool is, some schools can't get substitutes. During my one year out of the classroom I witnessed this firsthand at a school to remain nameless. I'd estimate that three-quarters of the absences meant splitting a class. That only happens occasionally at my current school.
SFUSD used to have "site support subs" at the STAR schools, but that funding evaporated. Now they have "core subs" (which has been around for a long time, I think): guest teachers who agree to take jobs at hard-to-substitute-staff schools. Unfortunately, being willing to take such a job and being able to do it are two different things.
Many of the subs inflicted upon my students have been decent, but it's the bad ones that stick out. Like the one who left me a note that my students were "awful". I don't care what they did - that's not okay. Or the one who left half an hour early, or the one who fell asleep (luckily, neither of these were in my room). After an illness I came back to a trashed classroom. A lot of things stored up high - out of students' reach - were particularly messed up. A little questioning informed me that some of these things had fallen during attempts to get them as the kids led themselves through various routines. What was the guest teacher doing as they climbed on chairs to retrieve calendar tags, readers and whatnot? Reading the newspaper. The paper and the sub's coffee cup were thoughtfully left for me to clean up. I was especially irritated to find that the coffee had been spilled all over my lesson plans (helpfully labeled "SUB PLANS" with a red trifolded paper), since this same guest teacher claimed I didn't leave any.
For guest teachers who can't return, there is a process for "blacklisting". Yet too often it seems not to go through; there have been cases whereupon a substitute comes to our school site and is immediately sent packing.
This is not really a solveable problem, unless teachers are somehow able to convince all friends to have summer weddings, have families who are immortal, are made immune to all illnesses and are cloned for maternity leave and whatnot. I'm crossing my fingers I don't have any major illnesses this year; having a Resident will also make a big difference.
*I have an outstanding dress to wear, too, and an iron-clad agreement that we can visit at least one designer concession that I cannot visit in San Francisco.