read works:
Search by Skill and Level: www.readworks.org/books/passages
Paired Texts: www.readworks.org/books/passages/paired-passages
Paired Texts: www.readworks.org/books/passages/paired-passages
front row ed:
Articles available at 5 levels: classroom.frontrowed.com/#ela/articles
k12 reader:
Content Area Articles Grouped by Grade Level: www.k12reader.com/subject/reading-skills/reading-comprehension/
Articles Grouped by Skill: http://www.k12reader.com/subject/reading-skills/
Articles Grouped by Skill: http://www.k12reader.com/subject/reading-skills/