Last week, there was a foul mood afoot.

Our oldest, who is typically a laidback, agreeable 10-year-old, sounded more like a grumpy old man. It was as if his glass half-full had spilled, and he’d stepped in the puddle with sock feet.

Noting his sour demeanor after school one day, I said, “Wow, you’re in a bad mood today. What’s going on?”

But he was in no mood to talk, so his younger brother chimed in and off ered his own diagnosis: “It’s probably the adolescence, Mom.”

“The adolescence, huh?

Does the adolescence put you in a grumpy mood?” I asked, as the brooding kid did his best to ignore us.

“Yeah, I think that’s what it does to you,” Jack said, clearly relieved that he’s still young and hasn’t yet contracted the dread disease.

So I let the issue drop because sometimes the best cure for a negative mood is a little time and space to work through it. But I’ve been noticing lately that this kid who was once optimistic and full of wonder and ambition seems a little disillusioned - not in a bitter, angry way. It’s more of a resigned sadness, as if he’s beginning to fi gure out that the world is not Disneyland. Things aren’t always fair. And sometimes life is disappointing and hard.

This new awareness is probably an inevitable part of growing up, but that doesn’t make it any easier to watch as a parent. In order to empathize, I try to revisit what fifth grade was like for me. The schoolwork got harder. Teachers expected more. The tests were trickier. And suddenly the social food chain was a much bigger deal than ever before, and navigating it made me anxious and edgy.

Status mattered more.

Brands mattered more. And coolness was critical.

Girls “liked” boys, and boys “liked” girls, even though most of us had no idea what the “liking” was all about. Some girls were mean and manipulative, and some boys threatened to beat up other boys. Social clumps started to form - the popular kids, the nerds, the weird kids, the sports stars,the goody-goodies, the mean kids and then lots of regular kids fl oating somewhere in the midst of all those cliques. The playground was no longer about freeze tag and monkey bars. It was complicated and sometimes emotionally exhausting.

I was always glad to go home after the final bell and escape the tween drama. But even at home, things were diff erent. My fi fth-grade awareness of the world made me notice that my parents were sometimes annoying, too, and I was convinced that their personality change had nothing to do with my own frustration and swirling preteen hormones.

So maybe fifth grade is one of life’s fi rst reality checks.

It’s when we find out that growing up is not always as fun as it looks on the Disney channel, and none of us escapes it completely unscathed.

Watching this process has given me a whole new respect for this stage of the parenting game.

We sometimes think the toughest stuff happens during the baby years, when we’re sleep deprived, changing diapers and making sure they don’t eat dirt. But the challenges change as the kids do.

I once heard a parenting guru say that our job is not to move the boulders out of our kids’ path but to help them learn how to climb over them. And that’s what I’m trying to do. But there are times when all I want is to climb into a steamroller and pave the way ahead of him - eliminate the hurts and struggle and protect the tender heart.

GWEN ROCKWOOD IS A SYNDICATED FREELANCE COLUMNIST. HER NEW BOOK, “REPORTING LIVE FROM THE LAUNDRY PILE: THE ROCKWOOD FILES COLLECTION,” IS AVAILABLE ON AMAZON AND AT NIGHTBIRD BOOKS.

Life, Pages 9 on 12/05/2012