Government Resources and Opportunities
You can find funding opportunities in a variety of government departments and agencies: almost every agency has them. Check them individually in organizations of interest to you.
Note that while many of these opportunities sound as if they are meant for students in STEM disciplines, they also may be open to students in other disciplines including business, communications, policy, law, etc.
federal government programs must be listed on either grants.gov or benefits.gov – the only problem is that these sites
include EVERYTHING and are a bit of a mess.
Benefits.gov: list of scholarships, but not comprehensive
Grants.gov: more complete, but must search by
Jobs.gov: can include some of these opportunities, so worth a look
Science.Gov: Internship and fellowship opportunities in science
American Association for the Advancement of Science (AAAS) fellowships
Department of Energy (DoE) Scholars Program, Science Graduate Fellowship Program, Computational Science Graduate Fellowship, and others, plus the programs at the national labs. Also internships.
Department of Homeland Security (DHS) Scholarship Program and other opportunities
Environmental Protection Agency (EPA) fellowships
Library of Congress
National Academy of Sciences (NAS) fellowships
National Aeronautics and Space Administration (NASA): NASA Undergraduate Student Research Program (USRP), Graduate Student Researchers Program (GSRP) and others, including those at the individual labs
National Defense Science and Engineering Graduate Fellowships (NDSEG)
National Institute of Health (NIH) undergrad and grad, with a variety of institutions, US and UK
National Science Foundation Graduate Research Fellowship (NSF GRF): the biggest at NSF, but there are a variety of undergrad, graduate, and supplemental programs. Start here, and you can also search "scholarship" and "fellowship" for possibilities.
National Security Education Programs (NSEP): language and culture study opportunities
The Science, Mathematics And Research for Transformation (SMART) Scholarship for Service Program, with a service commitment
U.S. Nuclear Regulatory Commission (NRC): search "fellowships and scholarships"