Here are some environmental organizations doing great work on behalf of our planet…
350.org: http://350.org/
Earthjustice: http://earthjustice.org/
Environmental Defense Fund: https://www.edf.org/
Environmental Working Group: http://www.ewg.org/
Friends of the Earth: http://www.foe.org/
Greenpeace: http://www.greenpeace.org/usa/
Natural Resources Defense Council (NRDC): http://www.nrdc.org/
Nature Conservancy: http://www.nature.org/
Rainforest Alliance Network: http://www.rainforest-alliance.org/
Sierra Club: http://sierraclub.org/
Surfrider Foundation: http://www.surfrider.org/
Waterkeeper Alliance: http://waterkeeper.org/
The Wilderness Society: http://wilderness.org/