Use Ulrichs Web to check whether or not a journal is peer reviewed. Look for the term "Refereed".
The following databases are good places to look for biology articles. The first two are the most useful for your insect projects, while the following two cover a variety of related science disciplines. Most databases contain a mix of peer-reviewed/scholarly articles and popular articles. Keep these tips in mind when searching:
To see all the University of Nevada, Reno Libraries' databases: A-Z Database List