For once, the classroom was silent. All heads bent, all pens moving, all brains ostensibly engaged. I flitted around the room bestowing encouragement.
Then I got to Andrew. Andrew had written three words in 24 minutes. He was averaging one word every eight minutes. A decent stonemason could have carved them in less time.
I shared some of these observations with Andrew, who registered only mild disappointment when I presented him with a sand timer, a target mark in his book and a reminder that unfinished work would be finished in his break time.
Although every school year presents you with 30 new and unique individuals, some things don't change. You will inherit some children who go at their work like a bat out of hell and, after 20 minutes, present you with four pages of barely legible, unparagraphed script containing precisely two coherent sentences. Others will produce thoughtful, mostly comprehensible work. And there will be some for whom producing any form of writing is like getting blood out of a haemophobic stone.
Last year, Jacob was that child. Jacob was lovely: polite, cheerful, popular. We suspected he was pretty bright but getting evidence to prove this was near impossible.
Jacob displayed an almost pathological dislike of putting pen to paper. Not for him the panic-inducing onset of time's winged chariot at his back. As all around him joined the race against the clock, Jacob gazed out of the window, studied his ruler and generally did whatever he could to avoid making contact with his exercise book.
"Why hasn't this child made expected progress?" I was asked, as Jacob's name flashed up bright red on the spreadsheet.
"It's not that he's not capable," I said. "It's getting him to produce enough work. He's just really lazy."
Wrong answer. Spreadsheets cannot understand laziness. Clearly my lessons were not stimulating enough. What was I doing to tackle the problem? I outlined my strategies: stickers, timers, reward and penalty systems, liaising with home - the list went on. The truth was, my teaching assistant and I were running out of ideas. And I knew I wasn't the only teacher to have struggled with him.
"I gave up," admitted one. "You sweat blood, but if they're determined not to work, your effort is for nothing." I hoped she was wrong, and that Jacob would one day morph from tortoise to hare.
Anyway, I now have Andrew to work on and I've not given up hope. Today he may have produced only three words but yesterday he wrote an entire paragraph in under 20 minutes.
But the overall problem remains and until Apple devises an app that flashes "this child has been idle for three minutes" over their heads, I have my universal back-up plan: to strive, to teach - and not to yield.
Jo Brighouse is a primary school teacher in the Midlands