If you aren’t graduating this May, or even if you are, one option to consider is looking for a summer internship experience. Some internships are paid, others are not, but both give you an opportunity to apply your skills and knowledge while learning something new AND building your resume.
Here are some website to visit for internships in various ‘green’ fields. Greenbiz.com and treehugger.com also offer job boards that you can sift through for internships. Good luck!