Reading Passages with Questions (New topics added daily)
These are all completely free and contain high-interest reading passages with follow up questions right there online! You can search for topics by theme, topic, genre, etc.
News ELA (Current events topics added regularly)
Another free resource with searchable and organized reading selections and online comprehension questions, too. You can even pick a topic and then choose what reading level you want to see that article on.
Reading and Listening:
This website has tons of reading (with audio!) sources for kids to use online at home.
http://www.teachersfirst.com/par-read.cfm
Interactive Reading Games
This website contains fun games to increase reading comprehension skills.
http://mrnussbaum.com/readingpassageindex/
Reading Help
Resources for all ages of kids and extra tips for parents to enforce reading at home.
http://www.readers.com/resources/education/kids-online-reading-games/
High-Interest Reading Passages on Current Topics
Kids can scroll through and search for topics that interest them (comprehension quiz for each one, too!)