- Ask a Marine Science Expert - Email your question after checking the archive of previous questions and answers.
- Ask a Rocket Scientist - Explains design, technology, aerodynamics, history, space travel, and other topics related to aerospace engineering.
- Ask A Scientist - You can ask a scientist a question on the WWW MadSciNet: The 24-hour exploding laboratory.
- Ask An Aviculture Expert - Birds and bird care questions. Not a substitute for a trip to the vet.
- Ask an Earth Scientist - Experts at the U of Hawaii answer questions about volcanoes and igneous rocks, earthquakes and seismology, natural disasters, geochemistry, the environment, pollution, hydrology and water quality, minerals, gems and crystals, geophysics, sediments and sedimentary rocks, and just plain ol' geology.
- Ask Dr. Science - Scientist answers a daily science question.
- Ask Mr. Water Wizard - Do you have questions about water? Questions about water quality in some nearby stream or lake? About drinking water? About water quality testing? About aquatic life such as fish, turtles, snakes, and insects, in your local waterways? Mr. Water Wizard can help.
- Ask Shamu - Ask and read archives of questions and answers. Mainly about marine biology and the environment.
- Ask The Space Scientist - Ask a question and check out the archives for the many questions asked at this site.
- Curious about Astronomy? Ask an Astronomer! - Browse archives of previous questions and answers, or submit a question to be answered by astronomers at Cornell University.
- eNature: Ask an Expert - Naturalists answer questions about nature and wildlife.
- How Things Work - Ask about almost anything related to the physical world, and check the well-organized archives for answers to previous interesting questions.
- Illinois State Geological Survey - Ask an Expert - Directory of geologists and geology questions.
- NEWTON Bulletin Board System - Ask-a-scientist service designed for K-12 teachers and their students - operated by the Argonne Nat'l. Laboratory, Div. of Educational Programs.
- Physlink - Ask Experts Physics and Astronomy Questions - Ask questions and check out the archives, organized by topic.
- PhysLink - Ask the Experts - Post physics and astronomy questions.
- Science Buddies: Answers to Your Science Questions - Ask questions and get help with your science fair project.
- Science Questions & Answers - Expert responses to questions on biology, chemistry, geology, and other branches of science.
- USGS - Ask A Geologist - Ask earth scientists at USGS questions about volcanoes, earthquakes, mountains, rocks, maps, ground water, lakes, or rivers through email.
- What is What - Aims to give you easy answers to everyday questions. We define words, acronyms, and ideas. We have a computer-related and open-source slant.
- WonderQuest with April Holladay - Check out the archives at WonderQuest, or ask a question for answers to conundrums about the world around us.
- Math (3)