Hey, they hit the jackpot. They invaded the U.S. and are rewarded with free babysitting at a cost of 8 grand a year to the NorteAmericanos. Plus free food under the school lunch program. Plus the kiddies dropped on U.S. soil are allegedly citizens of the United States (we won't call them "Americans", because even they know that's a fraud).
And best of all, they get the schools to themselves. Most Americans don't want their kids outnumbered by illegal alien children (because of the hatred that Mexico has for America, it's not safe for American children to be there), so they pull their kids ASAP. But they still have to pay the property taxes to support Los Mexicanos. And then pay big bucks to go to the private schools or move.
Great deal, huh? Kinda like extortion.