VolunteerMatch.Org
All Areas Volunteer Opportunities
VolunteerMatch.Org is a great website to find volunteer oppurtunities in your area. You type in your locattion into the search bar, and use the tag "environment." Be sure to contact the organization about the event to make sure it is going on. Good Luck!
United Planet
Abroad Volunteer Opportunities
United Planet is a place you can use to find volunteer oppurtunites aborad. Although it may be hard to go abroad and volunteer, but you can do it in small bursts. Perhaps a family vacation? Find opportunities here! Good Luck!
Habitat for Humanity
Building
Habitat for Humanity is not necessarily an environmentally active organization, but there are some environmentally friendly projects that you can partipate in. Additionally, it's a great oppurtunity to help people who need it!
CatchaFire
Using Your Professional Skills to Match you with Opportunities
Although not used necessarily for environmental events, CatchaFire.org is a great website for professionals to use their skills in their volunteering. For example, if you are a computer programmer, you could teach computer programming to help other kids.