Some time ago, I was a designated pick-up parent for a friend. At that time, we had a 'secret word' system in place. The secret word was known to me, the child, the child's mother and the day care operators, period.
Sandra, Polly's Mum (they were British) was in school at the time and her schedule was often late. Her husband, Robert, was a research chemist unable to leave his job at a moment's notice, so there were a few times when I would be called upon to pick Polly up. No id other than the 'secret word' was needed--no signing in--or anything else. I simply went to the office, said I was there to pick up Polly, and gave them the 'secret word.'
I don't know what system is in place now, but that one seemed to work.
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Tomorrow's just your future yesterday. Craig Ferguson