Please don't start outside the Primary School gates at 3:15, though!
It's all about exposure to nice kids in a controlled environment. We need to teach appropriate behaviour to BOTH the puppy and the child, and be there to supervise, especially with kids under 5. Puppies have good friendly intentions, but sharp teeth. Kids have good intentions, but can be too rough, or too familiar. Kids should not pick puppies up. They squirm, and it's easy enough for an adult to accidentally drop the pup. Encourage the child to sit with the pup on the floor.