Every group of students I have ever taught included two or three "knot-heads." You know, those difficult kids who--either by nature, or by design--seemed to conspire to make it difficult on me. Every once in a while, you get a group with eight or nine knot-heads...that's fun too! ("There aren't enough corners to spread them out!")
Sometimes it isn't the kids at all. Sometimes it's the parents. I've had a few classes in my time as a teacher where I've thought, "I wish this was a boarding school...then I would only have to work with the kids, and not deal with these parents!" We sometimes joke about helicopter parents, but this can be very dispiriting as a teacher.
Unfortunately, sometimes the difficulties aren't in the students or the parents, but the colleagues or administrators that make your life rough. Colleagues who seem to be out to thwart your innovative idea, administrators who give you just enough rope to hang yourself...talk about sucking the joy right out of the classroom!
And that doesn't begin to touch the pressures from society: people who decry teachers as lazybones, people who think unionized teachers are just out for more money, politicians who pass laws that put incredible burdens on teachers in the name of "raising standards" without really understanding what the job is like...all of these can make the already demanding profession all the more difficult.
There are days when I think all teachers need to pray the serenity prayer attributed to Reinhold Niebuhr:
God grant me the serenity to accept the things I cannot change,Don't we all need a little more serenity, a little more peace in our lives?
Courage to change the things I can,
And the wisdom to know the difference.