...you may want to check out this Crossway series of books called
Hymns for a Kids Heart. Co-written by Joni Eareckson Tada, nicely illustrated, and edifying, these books explain the story behind each of the hymns and what they teach us. They also come with CDs of the hymns being performed. Especially for someone like me--who grew up utterly bored with hymns--these books make for a wise investment in the next generation.