I think this line really showed your true intention
“Now I need to keep up with the Kleins and the Schwartzes and take my whole family away to Great Wolf or Florida???”
This has nothing to do with you feeling that the kids have too much free time and everything to do with that you feel pressured to exert yourself financially in order to appear as part of the community..
My advice to you is stop caring what anyone else thinks of you and your family…apathy in this situation will set you free.
And knowing the day schools they would probably charge a “winter break cancellation surcharge” therby making tuition even more expensive.
Let your children have a childhood and leave winter break alone