The answer is...it depends!
A good starting point is to apply the CRAAP test:
When was the information published?
When/how often has it been revised?
Do you need information that is super current, or will older information work?
Do all of the links on the website work?
Does the information answer your questions?
Who is the intended audience?
Is the information at an appropriate high school level?
Is there too much or too little information?
Is the author qualified on this subject? Are they an expert in this field?
What organization(s) is the author affiliated with? Is the organization reputable?
Does the url reveal anything about the author or organization? (.com, .edu, .org)
See the video below, "Deciding Who To Trust," for a more detailed explanation!
Where does the information come from?
Is the information supported by evidence?
Is the language unbiased and free from emotion?
Lateral reading: can you verify the information in other sources? (see the video "Lateral Reading" below)
Are there a lot of spelling/grammatical errors, typos, or formatting errors?
Is the purpose to inform, teach, sell, entertain or persuade? Is this purpose clear?
Is the information fact, opinion, or propaganda?
Are there any biases (political, religious, personal, etc)?
Reality: Wikipedia can actually be a great source...if you know how to use it! If you practice lateral reading (see the video "Lateral Reading" below) and apply the CRAAP test, Wikipedia can be a great starting point for research. And here's a research hack: the references linked at the bottom of a Wikipedia article can also be excellent resources to check out! See the video "Using Wikipedia" below for more information so you can become a more savvy Wikipedia user!
Reality: This may be true...sometimes. .Org sites are usually run by non-profit organizations and .Edu sites are usually run by colleges and universities. These types of sites tend to have a higher standard for the information they present, but not always. Likewise, .Com sites can provide valuable, accurate, reliable information (and many do!). Like with any site, you will still want to practice lateral reading and apply the CRAAP test!
Reality: Everyone is biased, and every site is biased. Your goal as a researcher is to understand the bias present in the information and try to choose information with minimal bias. For some projects, in fact, bias might be necessary -- such as in opposing viewpoint papers and debates.
Check out the videos below from John Green's Crash Course series to learn more about finding effective (and efficient!) sources for your school projects.