20/02/2015 10:29 GMT | Updated 20/05/2015 10:12 BST

I Spy On My Children's Friends

Young woman crossing her fingers behind her back

It takes a certain amount of subterfuge. I wait until no one else is about: the kids are watching TV, perhaps; my husband not yet home from work. I sneak to the hall cupboard, listening all the while for the tread of footsteps. The cupboard door open, I search through pockets and rifle through bags.

I'm not looking for telltale receipts, or lipstick on collars. The evidence I'm after is far more important; far more useful.

I know how my children are getting on at school, but how do they compare with their peers? Teachers are tight-lipped, and no parent's going to admit to little Johnnie being below par, so there's only one way to find out: sneak a peek at their book bags.

I know it's wrong. I know that every child learns at their own pace, but nevertheless I can't help myself from snooping in school bags whenever the opportunity arises. I tell myself that's not what I'm doing; that I'm opening my son's friends' bags for another reason entirely. I'd better pop those gloves safely away, I think or perhaps I'll wash out that lunch box, and save Daisy's mum a job...

It's all a ruse. My fingers creep towards the reading diary, flicking guiltily to recent entries. Stage 8 books? We're only on stage 7! Oh, but wait: they've not long moved up, and I'm sure they're an autumn birthday. Yes – six months older, at least. So we're okay, right?

It's just a benchmark, that's all. Nothing more. Just a guide to reassure me my children aren't hopelessly behind.

"Kids learn at different speeds," my friend Charlotte says, horrified by my snooping. "You're not going to learn anything by looking through book bags – you don't have any context." Charlotte's children are two and four. They're yet to start school, and I'm convinced Charlotte will change her tune once her children start bringing home reading diaries. "I won't," she insists. "I'm not interested in what other children are doing – only my own. What difference does it make if their friends are top of the class? It won't change anything for my own kids."

But I'm not the only one who takes a sneaky peak through my kids' friends' school bags. "I don't do it all the time," says Andrea, whose daughter Caitlin is in year two, "But I have to admit to looking at the reading book of one child in particular. Her mother is so infuriatingly smug, and always going on about how brilliant her daughter is. When I looked in her book bag I discovered she was still working her way through books my own daughter finished a year ago. I couldn't give two hoots what reading stage she was on, but at least now when she brags about her daughter I don't start worrying that my own child is falling behind."

"We all do it," agrees Emma, mother to two boys aged nine and seven. "We just don't talk about it. It's human nature to be curious: I quiz my boys all the time about who's done what at school; what people have in their packed lunches; what learning 'sets' their friends have been placed in. But the boys forget so much – it's just too tempting to look through their friends' book bags instead."

Angela is a primary school teacher, responsible (among many other things) for writing notes in reading records. When I confess my guilty secret she laughs. "You're wasting your time," she says. "Discovering that another child is on a particular reading level, or has been given a different set of homework tasks to your own, teaches you absolutely nothing about your own child. You'd have to analyse every single book bag in the year to get any sense of perspective, and even then I'm not convinced you'd get it. If you're concerned about your child's progress, speak to the teacher – they're the only one with the information you need."

I'm suitably chastised. Searching through my children's friends' school bags has clearly been a waste of time. Besides, according to father-of-one Matthew, I'm searching for entirely the wrong thing: "Never mind the reading records," he says. "It's the letters from the head teacher you want to find. Steam open a letter filling you in on Perfect Peter's behavioural problems, and you'll have enough gossip to last you the rest of the term." I don't doubt him, but intercepting letters is a step too far – even for me.

A sneaky peek in a book bag isn't so bad though, is it? Checking up on the progress of my children's peers is just part of keeping my own kids on track, and I'll bet far more parents do it than let on.

Are you a book bag snoop?

More on Parentdish: How your child will learn to read - and what you can do to help