You remember when you were young and curious? Oh that time has came and passed? It is understandable, I feel that way too. But for those who are still curious about life, we have this Encyclopedia of Life. It showcases everything from insects to animals to bacteria to whatever you can think of.  You can explore the wonderful world of life in detail not found anywhere else. All these are facts, figures and even statistical data are from reliable sources. And we are not talking about one or two species, we are talking about the whole shebang. There are over 1.9 million known species throughout the world. They have partnered with many museums and organizations throughout the world to showcase science, nature and whatever there is to showcase. Try this, everyday visit this site once to learn about nature but just be prepared, tomorrow you will be amazed once again. And you get to understand life on our lonely little planet. If you like, you can also donate directly to them.

The Rainforest Foundation supports people living in and around the world's rainforests to protect the environment and fulfill their rights to land, life and livelihood. The work of the Rainforest Foundation spans all major tropical rainforest regions with projects in 18 countries. - 
The Rainforest Foundation

Barcelona Field Studies Centre offers geography, biology, ecology and environmental field studies programmes throughout the year. Field study sites include Barcelona and the surrounding Natural Parks. - 
Barcelona Field Studies Centre

Eco-Cell. Fundraising made easy. Recycle used cell phones to raise money for your school or local project. Find out how recycling cell phones can benefit society in general. Help others by recycling phones. - 
Eco-Cell

This non-profit site contains articles about rare tree species native to the eastern United States. For each species, there is information about its characteristics, its habitat, its native range, and its rarity. There are also ideas for how it can be used in the home landscape. - 
Tree Trail