Mine go to school/care. Both boys birthdays fell on weekdays this year. Evan wore his badge with 6 on it & the one that had Birthday boy. Everyone made a fuss etc.
Glenns fell on the one day he goes to care & I took in a cake at the end of the day & they had a "little party" for him.

To me you stay home from school when your sick & thats that. Your birthday isn't a sick day. PLUS How boring is it to sit around & watch mum do the dishes, washing etc on your birthday when you could be running around with your mates at school.