K-12 education Common Core standards place a greater emphasis on the study of nonfiction literature.
To find nonfiction for YA readers at CSULB, use OneSerach, in the first box select "location" and enter "childrens nonfiction", and do a keyword search on your topic. The best way to determine whether a nonfiction book is appropriate for your age range is to go look at the books themselves.
YALSA (Young Adult Library Services Association) selects one book each year as the best Non-Fiction book written for young adults. This award is a fairly new award, the first was given in 2010. There are also finalists and nominees which are all worth looking at.