At Schweitzer Engineering Laboratories in Pullman, Wash., workers take classes in algebra, physics and writing in the factory complex and can check out books from a company library.  AT&T Inc. is investing more than $1 billion to retrain over 100,000 workers through a patchwork of classes and programs that are redefining the Dallas-based company.  And Atlanta-based aluminum products maker Novelis started a school within the company to impart lessons pulled from the factory floor with a faculty and nine “deans” to oversee it.  Why? A new engineering graduate hired by Novelis took five years to get up to speed.