Project Exploration has created a model for community-based organizations to follow in regards to mentoring middle and high school students in science. A Chicago-based nonprofit science education organization, Project Exploration's mission is to make science accessible to the public "especially minority youth and girls" through personalized experiences with science and scientists. At the heart of this work is youth programming, aimed at getting inner-city kids to think about science as a career option. Project Exploration targets students who may not already be academically successful, but are curious, open-minded, and passionate. In doing so, students are enabled to explore science, increase their scientific literacy, develop leadership skills, and expand their life and career options to include science. The science programs offered by Project Exploration, Junior Paleontologists, Services for Girls, and Dinosaur Giants, are starting points for long-term programming. After getting students interested in science, Project Exploration focuses on keeping them interested and building their capacity to continue that interest. Most students are involved with Project Exploration for at least two years, and a majority has stayed involved for five or more, beginning in middle school and continuing beyond high school graduation. Such long-term mentoring relationships have had significant impact in supporting students through high school and towards STEM careers: 96% of Project Exploration students have graduated high school; 61% have gone onto a four-year college; and 34% of all students and 43% of all women are majoring in science. Overall, Project Exploration students, most of whom are first-generation college bound and are not academically successful at the outset of their experience with Project Exploration, are ten times more likely to graduate from high school, go to college, and major in science than a typical Chicago Public School student from the same school. Project Exploration specifically recruits students who are historically underrepresented in science professions. These include women and minority groups, in particular those from low-income backgrounds; 81% of program participants are female, and 19% are male; 73% are African American, 25% Latino, 1% Caucasian, and 1% Other. By focusing on, and showing success with, these populations. Project Exploration is addressing critical issues facing STEM education today: inequality of opportunity, lack of diversity, and workforce development.