Example of research question: Do education programs in prisons decrease the recidivism rates of the incarcerated?
Keywords: education prisons recidivism incarcerated
Google search for: prisoners or inmates or incarcerated and education and recividism
Remember that the various levels of government (U.S., state, local) do studies and keep statistics on many topics you might be researching. Google Advanced searches allow you to limit your results to government (.gov) domains.
Google Advanced search, using the same terms but limiting the domain to .gov sources
Google Scholar searches limit your results to more academic sources than a regular Google search.