It really sounds like you’re drowning right now, and I’m so sorry you’re going through this, you’re trying to keep a roof over their heads, get them to school, and hold your job together, and you’re doing it all on your own strength. Anyone would be struggling in your shoes.
What you’re describing doesn’t sound like “naughtiness.”
Kids who go rigid, refuse to get dressed for months, and say they “don’t care” are usually overwhelmed, anxious, or struggling with an unmet need. Punishing/ threateningChristmas won’t fix that for you or them, it’ll just add more stress to an already heavy load.
Try
Speaking to the school.
Tell them exactly what’s happening in the mornings. Schools have family support workers, pastoral staff, and attendance teams who can help take some pressure off you and may even be seeing the same struggles during the day. In Wales we have Sure Start, there may be a similar team where you are. Taken them in their PJ's! I promise the school won't mind. I've done it.
Ask for a GP appointment.
Persistent refusal and going rigid can sometimes be linked to anxiety, sensory issues, ASD/ADHD, or emotional overload. Getting support early could change everything.
Remove the “battlefield” from the schedule.
Instead of “get dressed now or we’re late,” try (some won't like this but meh!)
Let them sleep in school clothes (lots of parents do this just to survive).
Put clothes by the heater/radiator so they feel soft and warm when they put them on.
Move the morning routine to a quiet, low-sensory environment, graduated wake up, go in 20 mins before, put on a light, no TV, fewer instructions at once. Give polite orders rather than request, not "please put your shoes on" try "put your shoes on, thank you".
Save your energy for the non-negotiable: getting out of the door. If brushing hair, socks, or shoes cause meltdowns, carry them and sort details at school if absolutely necessary. Survival mode is allowed.
Please don’t threaten Christmas, explain about work instead, try and get them to understand.
You’re a good mum. You’re exhausted, not failing, and there’s help available. You don’t need to carry this alone.