It was the weekly celebration assembly and, as usual, Charlotte and Jamie were up at the front, certificates and medals held high: all the achievements of their crammed extra-curricular home lives on full display.

They had earned their moment in the spotlight. They were both nice, kind children from nice, kind, supportive families. Families where children were read to, taken on educational trips and had activities, skills and experiences sent their way on a daily basis. It was the natural order to see these children emerge as winners.

But within the walls of a primary school exists a different kind of meritocracy: one in which the talents and efforts of every child have equal merit and are celebrated in equal measure regardless of their starting points or how well their families support them.

Well that’s the theory but this isn’t always easy to get right. Teachers are run off their feet. We’re human. When someone needs a name for the celebration assembly, or a child to show visitors around the school it’s natural to reach for our bright, articulate stars. Similarly, when we’re celebrating effort, how often do we zoom in on our more disruptive children or those who are struggling academically?

“Why is it that the quiet, hardworking children in this school are never rewarded but the badly behaved ones are?” I once had a parent ask me. She had a point. In our attempt to increase self-esteem and reinforce the effort = reward theory, our Friday assembly line-ups had begun to resemble a rogues’ gallery.

Being chosen for something - anything - is hugely important for primary-aged children, and their parents. Sometimes just publicly singling out a child for achieving something can be the push they need to achieve more and giving a disruptive child a position of authority can reap huge benefits.

But you have to do it well. In the past I’ve got it massively wrong. At the end of a frantic week I once omitted to print a certificate for a child in our good work assembly. He sat, unnoticed, on the bench until the headteacher spotted him and he got a quick handshake before the final song. His mum later told me she’d booked a half day’s holiday from work to come and watch him receive his certificate.

I’m coming to the conclusion that, if you’re going to dish out awards (and I don’t know of any primary school that doesn’t), then you have to distribute fairly. My job share and I have lists where we tick names every time a child is chosen for anything (even little things) to help us keep track of who is grabbing the moments in the spotlight.

Of course, you could argue that this devalues the merit: that some children are being rewarded less for effort than for the simple fact that it’s their turn.

But, setting aside events like sports day, I think a randomised but even distribution of rewards can work. For a start, I’m not sure we can always trust our instincts when it comes to selection. Primary children are, after all, a constant work in progress. I once took a punt and gave the biggest part in our class assembly to a disaffected, disruptive and fairly sulky dyslexic child who ended up learning his lines perfectly and absolutely shone in the role.

And, as the school reports of so many rockstars demonstrate, teachers are invariably poor at knowing which horse to back when it comes to predicting future greatness, so surely it’s better to hedge your bets and back them all?

Jo Brighouse is a pseudonym for a teacher in the Midlands. She tweets @jo_brighouse.