To the NEA "socialization" means mainly preparing kids for socialism.
When it refers to social skills, on the other hand, socialization means getting kids to learn about:
* what it's like to be bullied by bigger kids;
* what extortion of your lunch money is like;
* what being ridiculed by your fellow "students" feels like;
* how to learn to "hold your water" so you don't have to risk going to the bathroom and being beaten up;
* how to receive ridicule and condescension from teachers;
* how to obey authority and how to comply with their wishes, even if your rights or well-being or even sanity is being violated as a result;
* how to accept Ritalin when the brain-dead environment of school makes you act out, out of sheer desperation;
* which new hate words to use to replace the old hate words (e.g., how to call low IQ kids "speds" instead of "retards" -- same difference);
* how to hate whites, regardless of which race you are!
* how useless manners are;
* how to accept perversions of all kinds as "normal"; and the corrolary, of how to accept that moral behavior is to be considered unusual and deviant.
Well, there's more, but this is the main kind of socialization that a kid really learns in school.