In 2010, California enacted the Kindergarten Readiness Act (SB 1381). Prior to that time, California’s cutoff date of Dec. 2 for Kindergarten entry was one of the latest in the nation. In most states, children must turn five by Sept. 1 in order to start Kindergarten. California’s late Kindergarten cutoff allowed children as young as 4 years and 9 months to be in classes with children more than one year older. Rolling back the Kindergarten entry date a few months can make an enormous difference in the early years when children are rapidly growing and developing.