"Is a puzzlement!" says the King of Siam in the King and I. I like using puzzles for object lessons. I give each girl a piece of a puzzle as they come in the door or sometime during the lesson. As we discuss our principle, I will stop and have put the puzzle together. I hold a piece back so the puzzle cannot be completed. We can then discuss "finding the one" or making efforts to bring a YW back into activity. How incomplete our class is without her! We can discuss how each girl makes an important contribution to our class.
This object lesson can be used for so many different things such as pieces we need to put together to make ourselves Temple worthy. We can discuss how our talents contribute to making us who we are and can add so much more to our lives as we develop them. We can talk about how the teachings of the Gospel lead us, line-upon-line (piece-upon-piece) back to our Heavenly Father. We can discuss how Personal Progress helps us by building a testimony and learning to recognize the Father's hand in our life.
I usually just buy a child's 25 piece puzzle and that works well for our class. If you are more inclined, you can cut up a picture of the Temple or have a puzzle made of the entire class and then keep one of the pieces so that a face is missing. With some creativity, you may be able to find a way to make it work for your lesson.