Depending on what type of sources you need you will want to look in a variety of places. For credible but not scholarly sources you can do some basic Google searching using the Advanced Search to limit to .EDU sites You can learn how to do that by reading the far right column on this page http://libguides.starkstate.edu/content.php?pid=132310&sid=1557148
For scholarly research articles you can do some searches in a research database. On this page http://libguides.starkstate.edu/content.php?pid=132310&sid=1134622 you will see links in the far left column for both on or off campus access. I suggest looking in Edudcation Research Complete. When setting up your search 1) if off campus you will log in and click on Advanced Search under the single search box. Look for the section Limit You Results to Full Text or EBSCO Full Text if off campus and Scholarly Peer Reviewed 2) type in your search terms at the top of the page. Try typing in bullying in the first box and public schools in the second. That will get you started. Yo will probably want to play around with modifying your terms as you learn more on the topic. View your results and click on any you would like to look at. Once you click on the title look for the link on the left of the page to the PDF full text. That will open the article.
Good luck!