Well did contemplate cooking this morning but I just couldn't face it at 6am! So had a spoon of pink fluff and then at work at 7.30am had half a lidl roll and Brie
I don't know what your family circumstances are, and how you cook at home, but for the times MrB is elsewhere, and I am on my own, I now have the world's largest collection of smallish clip-top pots. Personally, I don't enjoy cooking for one, as much as cooking for more, so that means I will often have leftovers. The leftovers go into clip top boxes, and I either freeze or eat later. Most cooked dishes are safe in the fridge for 3-4 days (day 1 being the day of cooking, in my world), so it can ease the creative burden.
I'm not suggesting chicken vindaloo as your work day breakfast, but what about something like kedgeree made with cauliflower rice? Mocaronie cheese (again cauli), that sort of thing.
Additionally, you could buy a multi pack of chicken thighs (so much tastier and meatier than wings or drummers, in my view), and roast them - you could use spiced coatings if you like, or plain. Freeze individually, then when it suits, take one out of the freezer to fridge to defrost overnight for brekkers, with absolutely no cooking required whatsoever, on the day? You could easily cook 10 thighs in 45 minutes in the oven, another 15 minutes involved in packing for the freezer, and you have 10 meals in under an hour that are low carb and tasty.
I've also created salt grinders with various combos of spices and salts - salt and chilli, salt and garlic, etc. Just a couple of twists changes the flavour of something really simple. If I want something to go along with it, I almost always have a vat of home made coleslaw on the go, or someone suggested of the supermarket brands, the Tesco Everyday Value Coleslaw is lowest carb off the shelf. Half a tub of that (the tub is 250gr) comes to about 4-5 gr carb, if I recall. It's not as rich as my delicious home made version, but it's convenient, in an instant, and if I recall, under 30p a tub.
There are a million options, once you get your head around the need to think ahead and acquire the means of storing your treasures if need be. If your school fridge has a freezer compartment, you can even store your treasures there, taking breakfast out of the freezer box before going home the day before.