I introduce the elf to the children without touching him. It was later in the evening so I had to wait to register him but my internet provider serve failed so I was not able to print it that night to have for them in the morning. But that gave me additional time to make the authentication even more special. Later that day I showed them the kids the Adoption Certificate and the special sealed letter straight from the North Pole from Santa. My kids both agreed to name the elf Jerry after their favorite cartoon character from Tom and Jerry. lol
I also found this great link to a wonderful mom who thought of ways to incorporate faith and holiday tradition. She also included a special letter from Santa to explain how the elf will teach them more about Jesus and the true meaning of giving and Christmas. Elf On The Shelf Jesus Style you can click and print out your own letter.
Certificate of Adoption when you register your elf at Elf on The Shelf