OK....
[small]I work in IT support, so these moments are common. In a 16+ college, no less, so a lot of the moments are from senior staff who teach reasonably complex subjects and Should Know Better. The facepalm comes close to drawing blood when you've had too much coffee and therefore have an all too clear recognition that these people have managed to get out of bed, and travel across town to do their job, whilst also clean, clothed and fed without help of a carer, and will do the same in reverse in the evening, including operating a cooker and the telly...
But they still can't turn on a powerpoint projector with the equivalent of a stick, an ass-finding radar, and a large-print sheet entitled "how to find your own ass" attached to the relevant item by a bit of string. Or in the case of one lovely lady who never ceases to amaze, still-can't insert a DVD into the computer and play it without inexplicably switching the whole system over to the entirely seperate set-top-style DVD player and fruitlessly mashing buttons on its remote. What I want to know is how she made the disc (or any of her powerpoints) in the first place, as it wasn't a commercial one... Major hand-eye-brain communication disconnect somewhere, I'm in awe of how you can get things so wrong when the correct method is both a heck of a lot easier AND spelled out for you. Obviously missed her calling - should have gone into local government instead and found a happy niche putting traffic lights on roundabouts that should have been built as grade seperated junctions in the first place, if the previous postholder hadn't blown all the earthworks and concrete money on signalised gyratories.
(The "correct" method being either... turn on the dvd player and eject the tray, as you would one at home. insert disc and close tray, as you would with a normal one. turn the projector (ie the "tv") to dvd channel, and away you go. As you would. Simply in this case the "tv" is 80 inches across. OR, if you're already using the PC... eject dvd tray. insert disc and close it. wait 10 seconds. press "OK" when it asks if you want to play the disc. sit back and watch. What's so hard?! If that's beyond you for god's sake don't try using a microwave or crossing a road.)
Mind you working in frontline education does seem to take it out of people mentally, and it's easy to mock when you're working instead in the equivalent position of the guy who flies a Hercules on supply runs over friendly territory and occasionally patches up a blood-splattered assault rifle whilst at the base camp, which jammed when the panicked ex-owner did something dippy with the safety catch.
On the flipside of that, the OP's description is (sadly) just highschool kids being exactly that. It was pretty much that way when I was in a similar classroom 12-ish years ago. The thickest ones also tend to have the most confidence (as they have no concept of their own shortcomings, but plenty of that of other people's; it's similar for the real semi-savant brainboxes, but they tend to sacrifice the necessary charisma that is the thickie's saving grace and true power), and the loudest opinions, so they become the natural ringleaders, regardless of how accurate the stuff coming out of their mouth is. Everyone else except for one or two "er, what?" dissenters go along out of peer pressure - either the ringleader's mates, or wanting to be in that circle, or to just avoid being beaten up by them. They don't actually know or even care what the truth is or which is the "right" side.
Luckily most will grow out of it, or at least, without that critical condensation nucleii, will not feel confident enough to speak up and cause trouble, and can go on to be productive and even advanced members of society. The former ringleaders soon find adult life outstrips the abilities that served them well in the cosseted school environment, and descend instead into various positions where they can't do much harm, though sadly this isn't _always_ the case (and "not much" is far from being "no" harm, but I'm talking on a national level). Or they too can evolve, have a moment of "wow, i'm being a twat" and grow into more balanced individuals. I occasionally had it bad just for being a bit geeky and inconfident, an obvious target (no need to be gay... particularly in a boys school). But as the perps stopped being kids, many of them lost the taste for it, some actually became friends in a wierd way, and a couple even came out.
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