decent Xtian songs for kids?

I'm about to go do one of my favorite things, which is taking my guitar to St. John's Episcopal Church to play and sing for the little guys' Sunday School class. The 4-7 year olds are a great audience, though their attention span is, like, 3 seconds.

I find the repertoire for kids rather limited, though. I cannot abide any of the insipid Jesus music written in recent decades, but prefer all the old folk songs and spirituals, and the occasional English hymn.

Any suggestions? I'm desperate, since my own attention span is only marginally better than the kids'.