I introduced this poster as Elder Callister, a dear, dear friend of mine that is a full-time missionary visiting our Primary. I told the kids he had a sore throat so I'd be talking for him. He came to tell us about missionary work. He said that there were some item in the bag that he uses in his mission. I asked for volunteers to grab an item, purposely leaving out the missionary tag. When all the items were taken out, I pointed out that having these items doesn't make somebody a missionary then I asked the children what was missing. Answer: missionary tag, and that's when I pulled out the missionary tag item. I informed them that it gave the missionary a public identity that they were representatives of The Church of Jesus Christ of Latter-Day Saints with a special message from God. Also, pointed out that specifically for Elder Callister, it symbolized his testimony. Then I went over the 5 essential parts of a testimony:
"1. I know that God is our Heavenly Father and He loves us. 2. I know that His Son, Jesus Christ, is our Savior and Redeemer. 3. I know that Joseph Smith is a prophet of God. He restored the gospel of Jesus Christ to the earth and translated the Book of Mormon by the power of God. 4. I know that The Church of Jesus Christ of Latter-day Saints is the Lord’s Church on the earth today. 5. I know that this Church is led by a living prophet who receives revelation." (Liahona).
I concluded with my testimony, making sure to include all 5 parts ... I got all choked up because I mentioned that Elder Callister is a real person (he was the one who baptized me 20+ years ago) and encourage them to prepare to serve a full-time mission because there are more people like me out there.
For the Senior Primary group (ages 7-11), I added the door presentation below. I had them play pretend missionary and knock on "doors". I put the doors up on the blackboard and had a different child knock on each door and on the back was the response of the "person" who opened the door. The children would provide me their reply to the scenario. The kids seem to have had a kick out of this part and the replies were pretty awesome!! :)