ReadWorks.org has just released their newest update featuring STEM related passages for grades K-8.
ReadWorks.org offers free authentic reading comprehension passages that can be accessed on-line through a registered account. Seventy percent of their passages are non-fiction ranging in STEM and social studies topics. This is done with the intent of building students background and content knowledge. The passages can be used for whole class instruction, group work, guided reading, and independent reading. You can search for a specific topic, grade level, Lexile range or skill/strategy.
ReadWorks.org materials can be either printed or used with technology devices such as iPads/tablets and interactive whiteboards.
I posted a ReadWorks update in December featuring new content.