The link below is a great, free resource available with lots of passages and questions. These passages are available on many different topics and includes multiple choice and short answer questions. They now have passages available to increase reading stamina, which is really important as students get older and read longer passages.
http://www.readworks.org/passages-building-reading-stamina?utm_source=Email&utm_medium=Email&utm_campaign=030314%20Stamina%20EST