My primary focus in outreach is to underrepresented groups, which are predominantly females and minorities. The 20 million dollar question is why do females and minorities apply to computer science program at such a low rate compared to their applications to other majors (females apply to mathematics, biology, and chemistry in droves)? The prevailing thought is that females and minorities are both not exposed to the cooperative, problem-solving aspects to computer science while growing up, and are actively dissuaded by interactions they have either with computer science, computer scientists, or media representations of computer scientists.
Here are some outreach activities I have participated in, as well as some links to excellent resources for different all ages.