Here's the theme and four purposes of Primary in The Church of Jesus Christ of Latter-day Saints. I think it is important for all of us who work with the children to keep our focus on these important points. Everything we do should be fulfilling one of these purposes.
They say if the Savior came to visit church, the first place He'd would be to see the children. I feel blessed to be able to serve in Primary with the children who have such pure and kind hearts (even if they are wiggly and chatty too!).