I use the Common Core State Standards everyday when preparing lesson plans. Common Core has an app that can be put on an iphone for an easy search tool. I highly suggest the app.
The website that I found this week as a useful tool is readworks.org. I believe that this can be very beneficial to any and all teachers. It provides information on reading comprehension and it is all aligned to the Common Core State Standards of all 50 States. It is a free site with a lot of very helpful resources and many teachers encourage the sharing of this particular site. IT helps you to create your own lesson plans from it and provides many non-fiction material that is level appropriate.