Seattle-based Startup Weekend said this morning that it is launching a new effort called Startup Weekend Next, which will provide "pre-accelerator" startup training to prospective entrepreneurs. The group said the four-week class will help founders to learn about building a successful startup, based on content from Steve Blank, and which will be held in 350 cities worldwide. The new effort will be rolled out through Startup America, with TechStars providing experienced startup mentors to help coach entrepreneurs.