I think it's absolutely ridiculous to think that a 5/6 yr old child having a day off is a bad thing if it's only once in a while, and I'm a teacher.
I'm not condoning the "Mummy, I don't want to go to school today, we're only doing art and it's boring, lets go out instead!" scenario but rather the very special occasion/event. A show in the city at the end of term, Grandma visiting from overseas, that sort of thing.
Education at this age is supposed to be a fun learning experience and you are deluding yourself if you think that one day off is going to cause them to miss out on something fundamental. Concepts are taught over a long period of time, not in one lesson. And tbh, at this time of the year there's not much happening, curriculum delivery wise.
I'm sorry to rabbit on but I feel really strongly about this.
I've had instances of children getting so distressed about not being able to attend for a day, even due to illness, that I've had to speak to them on the phone to reassure them that it was OK.
I understand the need for setting examples, but if you set too rigid an example it can have extremely detrimental effects.