Citizen Science refers to a wide range of activities that occur near the interface between professional science and the public. This list is a subset of citizen science in which citizens can participate and actively contribute to data collection, analysis, and scientific research. Many of these projects rely on people's ability to classify objects and animals, others rely on environmental observations (and may be regionally specific), while others yet simply require computing resources. Zooniverse, Boinc, Scientific American, National Wildlife Federation, Planetary Society, and Sky & Telescope provide good introduction to the subject and include multiple links. Science for the People is proud to participate in The Citizen Weather Observer Program , The Weather Underground , The Radiation Network , and Stanford University's Quake Catcher Network and to support citizen science generally.

Asteroid Classification
Galaxy Classification
Cosmological Models
Composing a 3-D model of the Milky Way
Classical Dynamics
International Meteor Organization
Lunar Impacts
Lowell Amateur Research Initiative
Search for Neutron Stars
Stereo: Mapping the Sun in 3-D
SETI (The Search for Extraterrestrial Intelligence)
Transit of Venus
Target Asteroids

Air Quality:
Louisiana Bucket Brigade
Mapping for Change
Air Quality Egg

Ancient Lives

Biology, Ecology, and Medicine
Genographic Project (Human Evolution)
Human Microbiome
Human Microbiome II
Evolution MegaLab
Virtual Prairie
Malarial Control
Fight Malaria @ Home
Canine Cognition
Ecological Classifications
Orca sounds
Turing Sunflower
Human mathematical ability and age
Loon Survey
I spot (help confirming biodiversity observations)
Tag a Tiny (Tuna)
Zombie Bees
Tag a Tiny (Tuna)

Ice Pack
Ice Watch
Rink Watch
Old Weather Watch
Climate Related Citizen Science (list)

Earth Science
Sea Floor Explorer
Geo-Wiki Project
Yard Map

Citizen Weather Observer Program
Weather Underground
Cyclone Center
Sky Warn

Molecular Biology
Protein Folding
Genetic Medicine
Protein Sequencing
Protein Folding
Protein Structure
Molecular Medicine
Protein Ligand Modeling

Radiation Network
Gamma Radiation Monitoring
The Gamma-ray Coordinates Network

USGS NetQuakes
Stanford University's Quake Catcher Network
Citizen Seismology
EMSC Projects

Water Quality
Sierra Club Water Sentinels
World Water Monitoring Day

Wildlife Health Event Reporter
The Backyard Bee Count
Cornell Lab of Ornithology educators
Classify Wildlife of the Serengeti
Wildlife Sightings
Feeder Watcher
North America Bird Phenology
Plant and Animal Phenology
Monarch Parasites
Monarch Health
Collaborative wildlife Observation
Native Buzz
Monarch larva Monitoring