We have done two different hunts.
1. I painted large plastic eggs with gold paint. Each egg had a letter on it from the sentence "HE IS NOT HERE". The kids hunted around downstairs after church. When they found them they were to bring them to coffee hour and assemble the eggs in a carton to "unscramble" (pardon the pun) the message.

2. Last year we hid objects eg. a packet of seeds and gave the kids the clue, "Soon you will plant these in the church gardens". Once they returned with the item they got another clue. We used Easter symbols as much as possible but I have to admit that we could have done a better job of that when I read what others have written here. We just needed some activity for burning off some energy. Those chocolate egg hunts had not been going well in the past!
Blessings,
Hilary