This was a sharing time in primary. I adapted it a bit for our Family Home Evening. Get a clear bowl or clear glass pitcher and fill with water. Get two oranges. You could draw a face on the orange if you want too.

Put the oranges in the pitcher to show that they float. Go the scriptures in Ephesians and read thru the portion on the armour of God. You can include as much or as little of this as you have time for. Have class members come up with things both that strengthen or represent the armour of God, and things that weaken or distress the armour of God. Each time you discuss something that weakens the armour, cut a slice off of the orange peel. Keep going until the whole orange is peeled.

Keep the other orange whole. Float the two a few times during the lesson to see how they are doing. When the whole orange is peeled, the orange without the armour sinks to the bottom.