I'm putting these links here so I can find them again, but perhaps there are others who could benefit from this information.
This link is a reading level assessment. There are two word lists and the student simply reads until it is too difficult. Note that this doesn't judge comprehension. Billy was able to accurately pronounce the word "enumerate," but he has no clue what it means.
This link gives instructions for evaluating the reading level of a document in Microsoft Word. The one bit of instruction left out is that you then do a spell check, and it will give you the information after that is complete. There are many uses for such a tool. You could type in a few paragraphs from a library book to see if it is a good level for your student. But most useful, I think, is in evaluating the student's writing. It's nice for evaluating your own writing too.
To understand the Flesch Reading Ease number, go here.