Teachers emerge briefly, looking even more harassed than usual, then disappear back inside for another late evening. The tarmac is measled with piles of sand, covering evidence of yet another tummy-bug epidemic.
Yes, it is Christmas concert time again, and all the playground chatter is of endless cramped rehearsals in the school hall, of heart-breaking auditions giving budding young thespians an early taste of failure, and, of course, the blatant injustices when it comes to the lead parts.
Since half-term, education has taken a back seat as the school nativity play, or the even more time-consuming junior drama, takes shape. Spelling tests disappear, reading books remain unchanged, homework ceases. This would normally evoke the same response as a term-time week at Alton Towers.
But the benefits of less work are far outweighed by the penance required.
There are the agonies of the auditions. Dreams of standing up on stage with proper lines are shattered. Hopeful pupils are consigned to sitting on the cold hall floor, singing cross-legged with the masses, after failing to beat the sparkly little naturals who are up there year after year.
"We had to sit in the hall all afternoon doing singing practice - and we did it yesterday too, and it's soooo boring. And they won't even let you read a book through it," pupils snarl, as they stomp out of school, bad-tempered and frustrated.
"And FredFreda Bloggs has got the lead part again... and I'm doing nothin' 'cept singing, it's soooo sad."
"Keep your voice down," you hiss, as you drag them out of earshot and off to footballfencingTae kwon do.
I know that, come the big day, we will all be wowed and dazzled by the sheer professionalism of the productions. We will admire the confident acting and the harmonious cross-legged singers. But there is a growing number of us who would be much happier with each class writing its own low-key piece about the spirit of Christmas, requiring minimal rehearsal but involving every single child.
I'm sure some progressive, forward-thinking schools in the big cities do it already. But I cannot suggest it myself. I might do my little Johnny out of a part in next year's extravaganza.
Jane Davies is a parent of primary-aged children in south Wales