Generally speaking, most children start 4 year old kinder at age 4 then turn 5 during the year. Floss will be 5 in January, so she will be one of the oldest in her class, but most kids in her kinder class will also turn 5 next year. As a prep teacher, when faced with the decision to send them 'early' or be one of the oldest, I would be keeping them until they are older.