So back in the eighth grade (a good eight years ago) I thought of this scenario where the Marauders wanted to find a loophole for the ‘No students out of bed at night” rule. And I came to the conclusion that they would absolutely sit on their beds and levitate them throughout the corridors so that they were never actually technically out of bed. And it’s been eight years and I just remembered this headcanon and I still think that they absolutely would have done this.

someone please write a fic where they debate the technicalities of this with McGonagall

“Out.” McGonagall was practically vibrating, the tip of her hat quivering like a compass needle; from yearly observation, Sirius was reasonably sure its four Cardinal Directions were What Is Going On Here, Stop, Ten Points From Gryffindor and Detention, and there was no doubt the wind was currently blowing a strong North-North Detention. He grinned. Knowing they were going to lose eventually didn’t make this any less amazing; there wasn’t even room in the corridor for all four beds to float abreast, and Peter’s was behind his, listing like a boat in rough waters with his inevitable nervousness. Peter hated detention – the rest of them pretty much took it in their stride at this point. Besides, Sirius thought impatiently, he was enjoying it a minute ago. It was probably him giggling that woke her up. Or Remus, bouncing the end of his bed into one of the portraits by accident. That guy must have been pretty square in life; he went off like a roman candle.

Like always, in trouble, he felt giddy; it would be bad, but the consequences here were so easy compared to what he’d left behind that he could never help the hysterical weightlessness that came hot on the heels of the scandalised gasp of a teacher. Fifty house points still hurt a lot less than fifty other things. But James was talking.

“- and it’s good practice,” he was saying, leaning precariously forward over the edge of his bed, an earnest ship’s figurehead in striped pyjamas. “A simple levitation spell wasn’t strong enough, Professor, we had to do research.” The bed between them shook a little; Remus, laughing, trying to cover it up with a cough. James said research the same way Slughorn might say diet. Peter’s bed bumped into the back of his and it almost set him off, too. He bit the inside of his mouth, tried to focus on something not funny – James’s thin ankles, poking out of the ends of his pyjama bottoms, that would do. Guaranteed to stop him laughing, that was.

“Research,” said McGonagall, not at all the way Slughorn might say diet. “We did,” Remus protested evenly from a nest of blankets – nobody was seeing his ankles. “We spent four hours on it in the library. In a way, this is just a practical experiment.”
“Yeah,” said James, “Those are encouraged. Professor Flitwick was just talking about it on Monday.”

Remus looked at Sirius; Sirius looked back. On no account, Professor Flitwick had said on Monday, do any practical experiments outside of the classroom. He could feel Peter getting ready to say it, too; they both could, both turned to look at him at once. He’d been raising his hand. Sirius shook his head once, both discouraging and also giving him up as a hopeless case. For being the one who’d come up with the word marauders in the first place, Peter was awfully coy when it came to doing any actual marauding.

Being a person confronted with four large pieces of floating furniture suddenly seemed to become too much for McGonagall, and she snapped again, “Get down. Get out of those beds at once.”
“But Professor,” James explained patiently while Sirius’s stomach did that swooping drop thing again, “Then we really will be breaking the rules. No students out of bed. But we’re in bed.”
“Of bed?”
Out of her favour where I am in bed,” Remus murmured and Sirius let out an unnecessary and, in retrospect, unwise shout of laughter. (They’d done a dramatic reading of the play when Remus brought in a battered Complete Works after the last holidays; James still occasionally greeted bemused students with Do you bite your thumb at me, sir? and they’d got a good amount of mileage out of Swear not by the moon, the inconstant moon, as well.)

Later, the rules were amended to read or out of their bedroom, and they did all have detention, and there was a miserable business with a Howler, and they lost a significant number of house points – but it was worth it, for the looks they got when they explained what they’d done, and for Remus quoting Shakespeare in the middle of a crisis, and for James’s wretched ankles and his scruffy, innocent face as he almost fell out of his hovering bed. And for being one of four, Sirius thought, looking around at the others in said detention: Remus’s hair in his face, the way he gripped his quill like it was trying to get away from him; James frowning in concentration as he tried to clean up the inevitable ink stains he always left on the desk; Peter’s misbehaving roll of parchment that wouldn’t stay flat unless he leaned all of his weight on it. It was always worth it for being one of four.