"Launched in June 2013, Newsela publishes high-interest news articles daily at five levels of complexity for grades 3-12 using Newsela’s proprietary, rapid text-leveling process." Many articles are available in Spanish as well.

It's well worth signing up for the required free account to access this site.

NewsELA also publishes Common Core–aligned quizzes, attached to articles, "to develop nonfiction fluency and critical-thinking skills necessary to master the Common Core standards for informational text."