So many things make the job a delight. Certainly, working with a staff of talented, creative people who thoroughly enjoy each other's company reaps enormous rewards. The school runs like a well-oiled machine, and our website is filled with comments from past pupils who say how much they miss us.
But it's the children who make the job what it is. Although my school is in a deprived area, with huge social problems, I am constantly amazed by their cheerfulness, affection, resilience . and, most of all, their humour.
It's the humour, especially, that will stay with me long into retirement.
It was apparent from the moment I started teaching - in Islington in the 1960s - when the local inspector was testing the metric knowledge of diminutive Freddie, the local fishmonger's son.
"How many centimetres are in half a metre?" he asked, to which Freddie proudly answered: "Fifty."
"Good boy," said the inspector. "Now, how many of these tiny millimetres do you think are in a metre?"
"Wow," said Fred, "there must be fucking hundreds!"
LEA inspectors were replaced by Ofsted, and I was greatly amused by a colleague's tale of a child who'd misbehaved during an inspection and been sent to sit on the threadbare carpet outside the classroom for 30 minutes.
"I assume you've been naughty, young man," said a passing inspector. "What could your teachers provide that would make school a happier place for you?"
The boy looked the inspector firmly in the eye. "Thicker carpets," he said.
Even as an ancient head, I still teach, and Monday afternoons working on literacy with a less able group from Year 6 certainly had its moments.
Asked to write a story that might appeal to nursery children, Abdul decided upon The Magic Chicken as a title. After scribbling for several minutes, he suddenly appeared fazed. "How d'you spell bok?" he said. "Do you mean `book' or `back'?" I asked. "No, no," he said impatiently, "I mean the sound wot a chicken makes .. Bok bok bok . ".
Thomas, a highly intelligent eight-year-old, was at the other end of the scale. We admitted him without realising he'd already attended three other schools and was virtually uncontrollable. When he decided on his first morning he'd behave however he liked, I was forced to lead him very firmly from the classroom to the visitors' chairs outside my office, where he put his feet up and engrossed himself in a book.
My new school improvement partner was visiting for the first time that morning and, when she appeared, she looked sympathetically at Thomas.
"Hello," she said. "Are you here because you're unwell?"
"Nah," Thomas replied cheerfully, "I've just been assaulted by the `edteacher."
But sometimes, a child's comment can elevate you for days. Rachel, like Thomas, had also joined us from another school, where she'd had a lean time. After a successful term and a starring part in the school play, she smiled at me one lunchtime and said "Sir, I don't want this term to end."
"Why's that, Rachel?" I asked.
"Because," she said, "it's been the happiest time of my life."
After a comment like that, who could say that this job isn't the best in the world?
Mike Kent is headteacher of Comber Grove Primary, Camberwell, south London. firstname.lastname@example.org.