As a muslim we shouldn't celebrate birthdays and all the parents are encouraged to train their kids to follow this. For small kids who can't understand this islamic faith can celebrate the birthdays within the limit as described below.

The staff and students of the school are happy to offer the best wishes on student’s birthday. On their birthday students are allowed to wear a neat and decent casual dress. Students can distribute chocolates to their classmates during the break time.
During the school hours, no birthday parties will be allowed. No permission will be granted for distribution of gifts.