I signed up for 12x12 and Start the Year off Write. I've seen some great resources flying across the Facebook book groups. Here's a few of them:
A relatively new website that has a massive inventory of children's publishing topics. It's like a Costco for writers: http://www.kidlit411.com
Katie Davis (see video link above) has a YouTube channel with videos on various topics of kid lit, especially how to market yourself and build your *buzzword* platform: http://www.youtube.com/user/BrainBurpsAboutBooks
And finally, if you're meter challenged like me, here's Rhyme Weaver's link, a nuts and bolts resource for writing in verse: http://www.writingrhymeandmeter.com.
Have a fantastic weekend!