Church and Prayer
Daily Mass Readings, Morning & Evening Prayer
Diocese of Kalamazoo
American Catholic
Catholic.org
U.S. Catholic Conference of Bishops
The Vatican Official Site
Want to receive a daily quote from the Catholic Catechism or from the Gospels? Check out these links:
https://www.flocknote.com/catechism

http://flocknote.com/gospel
It's great because they just send you a little bit each day, and it has links to further reading if you want to learn some more. They also archive the entire set on the website so you can go back and see a particular section if you want to. Hope you find it interesting if you decide to do it.
Young Adult Catholic Sites
Busted Halo
Decide in Faith
Life Teen
Jesuit Volunteer Corps
Vocation Network