Week 1 Jesus Christ was chosen to be our Savior.
Have a lock and at least 10 different keys, 1 of course being able to fit and open the lock. Have questions, songs and scriptures having to do with the premortal world corresponding to the keys. Invite a child to come up and choose a key and answer the question or read the scripture (if it's a song, sing it all together). Explain that the lock is our happiness... what is the key that will give us happiness?? Whip out of your pocket the key that fits the lock and point to a picture of the Savior, invite a child to open the lock.
"When the great War in Heaven was fought, Lucifer, the son of the morning, came forth with a plan that was rejected. The Father of us all, with love for us, His children, offered a better plan under which we would have freedom to choose the course of our lives. His Firstborn Son, our Elder Brother, was the KEY to that plan." (Gordon B. Hinckley, in Conference Report, Apr. 2002, 107)