At my son's school, parents can only drop off at the curb (teacher aides are there to assist getting out of cars). You aren't even supposed to sit in your car to watch them walk in the door (couple hundred feet away) because it holds up the car pool lane.
Here in Florida, Collier County
You have to drive through a gate ,
stop at Guard house,
Camera on Guard house snaps picture of you and your car,
you have to drive around a big loop,
stop for 2 seconds child is to be in back seat,
teacher opens back door kid gets out goes through school gate,
picture snapped of child
then child goes to area with picnic table and sits with their class,
at 8:00 am teacher takes role call at picnic table
and gives report to office,
any child that is not there, their parents are called ASAP.
If your child comes late same thing only you have to park your car and Security Guard walks you and your child to office and child to class and you have to go to your car ASAP.
ETA: if you come late with your Child, you have to give the Guard house your DL and you get it back when you leave.