Kindergarten age requirements vary from state to state. In Arizona, your child must be 5 years old before September 1 of the year in which they wish to start kindergarten. If your child does not meet the standard age cutoff but will be turning 5 years old on or after September 1 but on or before December 31, you may apply for early admission. In Louisiana, your child must be 5 years old on or before September 30. Louisiana does not offer early admission for children who do not meet the age cutoff.