While you're doing Google searches to either narrow your topic or in order to dig up more information on certain subject, you want to be careful to decide if the information you find is trustworthy.
When it comes to science, nearly everyone has opinions: should we be labeling genetically modified food for consumer's awareness? What will fracking do for our economy or to our groundwater supply? Your job is to evaluate the information you can find through search engines such as Google to find the good websites--those written by authors with clear expertise, with up-to-date information.
Authorship: Who created this website? What is their background on the topic? Are they trustworthy?
Bias/Mission: Why was the website created? What point of view does the author or website have? Does that limit the facts they present or how the facts are presented?
Date: How old is the information that is presented? Is it still accurate?
Questions? Check out the COD Library's guide to evaluating information.