Thanks! I looked up both suggestions and these are great! Our district has a reading test that we give each quarter, but teachers bad mouth it all the time and say it's more of a vocabulary test than a reading test. Thanks so much!

Another interesting idea for a reading pre-assessment would be to have the students to a self-evaluation of their own abilities.  You could create questions where they rate their abilities on a 1-10 scale for categories like vocabulary, comprehension, critical thinking, but you could word the questions fairly simply, like:  "When I read material to study for a test, I remember mostly everything." 

This could be a great discussion point and provide some valuable student-driven data.

Depending upon where you teach, the school should have records of student reading ability as defined by their testing. In Illinois, our students take the ISAT and the PSAE tests. Both of these tests show reading ability. Outside of that, I did find an online site which offers online testing for reading (I am not familiar with the site, but it looks promising).

http://www.test4free.com/assessfam.asp

I teach eighth grade and my students take the GATES-MacGinitie reading test.  It evaluates reading grade level and vocabulary.  Then they retake the test again at the end of the year, so we can measure and chart student growth.  The test runs about fifty-five minutes, so it definitely is not quick, but will give you so much comprehensive information on students' abilities.