@laughoutlood,
That would not work because there would be CPS workers involved, as well as home visits, and you'd be telling the kids to lie. Bad, bad, BAD. Plus, the school would know from their Contact Information. Do not do this.
I suggest everything will be just fine because who in the world is willing to take 4 kids??? Nobody! Not even the relatives are able/willing to do that, so... just wait it out. Trust me, I know of what I speak. Personally. And even if they DID find a family, odds are it won't work out, so you guys will wind up with them again. Just make sure you always let them know you're willing to take 2 and Uncle Joe is willing to take the other 2. Believe me, this will work out for you in the end.
If all else fails, get a family lawyer.