By the end of year, read and comprehend informational texts, including history/social studies, science, and technical texts, in the grades 4-5 text complexity band proficiently, with scaffolding as needed at the high end of the range.

The idea behind this standard is the same as its Reading: Literature counterpart, so take a look at what we have to say about this standard over there. Just replace anything related to literature with non-fiction as you read.