I strongly believe that science is not just for scientists. What scientists investigate is only valuable if the greater community is involved and understands the significance. I have participated in many engagement efforts over the years, most notably pub talks, skype-a-scientist, and K-12 programming.
Science Pub Talks
I have given two different public talks at The Loft in downtown Lansing on wildfires of California and how people have moved plant species around the world. This popular program is run by graduate students in the Integrative Biology program.
I presented to the local community 
about wildfires and plant adaptation in Southern California. I have also given a talk about invasive plants of California. This program is organized by the Santa Barbara Museum of Natural History.
Skype-A-Scientist
I have had the pleasure of working with the Skype-A-Scientist organization for several years to connect with middle school to elementary school classrooms around the world. See more information about the organization here. One of the teachers from Missouri compiled a wonderful video about the experience.
K-12 programming
This question-based organization at UC Santa Barbara receives science questions from students of all ages and from around the world. Through this program I visited a local elementary school and examined smelly plants with 1st graders.
A program dedicated to 7th & 8th Grade Chemistry experimental design. We visited middle school classrooms and guided students through the scientific method.