At your child's school, what is/was the birthday ritual?

My son turned nine today, and we brought in brownies for the midmorning snack. My son sat in a chair, like a throne, while all the other kids sat in a circle around the room. I put a candle on the brownie, and lit is, and they sang Happy Birthday, except they added all these “cha, cha, chas” and a counting game at the end, and I think, some other things. They were all nice and polite, and said their thankyous, and some even complimented us on the brownies. Afterwards, there were two extra brownies (two people didn’t want them), and my son got to go wander around the school for a while, to find special teachers he’d had before to give them to. I recovered all the tupperware after that, kissed him good bye and left.