School Nurse question

How much experience is required to be hired in a school as a full-time nurse? I have been hearing conflicting information from various sources. I know 2 girls that I graduated with were hired the September that we graduated to be school nurses. I have been told that 6 months experience is required. Recently someone said that you couldn't become a certified school nurse in Delaware and work in a school permanently unless you have 3 years clinical experience. This doesn't make sense as previously stated 2 new grads were hired. Does anyone know? I know the Delaware School Nurse Association suggests 3 years and the Delaware School Nurse Manual also says 3 years but is this optional and up to the individual school?