EXPLAIN what it means to knock your socks off. That is means that you did so well that the person's socks fly right off! Of course, that wouldn't really happen, but you did sang so good that they also feel really good inside to, from head to toe!
Have song names inside the socks. Invite a child to pick a sock.
Ways to do this:
1. Invite teachers up and set the socks on top of their shoes. When the kids sing well the Teacher kicks the socks and send them flying.
2. Line up socks (made out of felt or paper to make them stiff) along the chalkboard ledge. Knock them off the ledge with the children sing well.
*Idea adapted from, Teaching LDS Children