Juggling Joe And His Talented Toe

I agree with Tracey about the rhythm, particularly in the final lines of at least half the stanzas.  If this were mine, and it were for a children's book, I'd concentrate on a smooth, infectious rhythm, ala A.A. Milne.  Lines like "With the world’s biggest toe" always seem to be upsetting the cadence that the preceding three lines establish.  Add to that the idea that juggling is a very graceful application of rhythmic motions, and you get an idea that maybe your own rhythm in writing this should be extra smooth, except perhaps in the stanza where he drops everything.  Of course, currently in that stanza, your rhythm is perhaps at its most impeccable.

Outside of that, I think this is an excellent book idea.  With a good illustrator, I could imagine kids loving a story like this.  I'd even consider adding more stanzas with an even greater escalation of ridiculous details - only because the idea is so ripe.