1. Metasearching using dogpile What I like about this is that on the page where your results are listed, it categorizes your results in ways that might behoove better research. If the student types in "global warming," then it asks if you would also like results that only focus on "causes of global warming," "effects of global warming," and so on.
2. Google Advanced Search Obviously, the more specific you search, the less work you have to do. Let Google do the work by spending just a little time creating parameters for your results.
3. Google Scholar This can be a little heady, but it has also led to some really interesting results.
4. Reading URLs What does a .org mean? .gov? .edu? What symbols may indicate personal sites? Reading the sentences of the URL is the first step in reliable searching online.