Being a teacher is back-breakingly difficult work. It is also extremely important work.
Obama is an intelligent man whose life and work experience sensitize him to class distinctions.
President Obama seems to think that you win by demonstrating that you're a more reasonable person than your opponents. It didn't work too badly, I'll grant, as an electoral strategy in the 2012 election.
Being superintendent or the superintendent's chief of staff is important work, but there's no chance it's as difficult as being a teacher, and I hesitate to say that it's as important.
The only agency of the federal government with a more demoralized workforce than Homeland Security is the Small Business Administration, a notorious turkey farm that should have been abolished years ago.