OK so let’s say that the peel represents the armor of God.
When you have the armor of God on, you float! (You are able to overcome temptation, trials, etc.) Another thing you could relate it to could be faith, and bring in the story of Peter walking on the water. Or instead of the armor of God, you could relate it to living worthy of the gift of the Holy Ghost, which keeps our head above the water and can protect us against deception.
But. . .
What happens when you remove this protective peel?
When you compromise your standards, or take off your spiritual armor, you sink.
Here’s a short video about the armor of God that could go along with the lesson.