I was a little offended by the suggestion that IS teachers don't work that hard. My husband is a teacher at an international school and 11-12 hour days are his norm too, plus plenty of marking/planning on the weekends. Maybe people think he doesn't work long hours because he gets home at 4:30 or 5 each day, but that's because he goes in to work super-early, and then once our son is asleep he works several more hours.
I would hesitate to infer that just because a teacher doesn't call to check in that means they don't care. I wonder if maybe you thought the teacher wasn't that caring before this incident and so it just proves what you already thought.
I don't think my husband has ever called home to a sick student just to see how they are, though he certainly communicates by email to coordinate work. But I think he's a very caring teacher ... goes out of his way to talk to students who seem down, give them lots of extra help before or after school, frequently gives up his lunch break to meet with a student, etc. There are lots of ways to show care and concern.
