In 1990, the U.S. Department of Education established a math and science initiative within Upward Bound, a federal grant program designed to provide disadvantaged high school students with skills and experiences that will prepare them for college success. The Upward Bound Math-Science (UBMS) initiative awards grants to colleges and universities to provide participants with hands-on experience in laboratories, computer facilities, and at field sites, as well as opportunities to learn from mathematicians and scientists at host institutions. By 2004, there were 127 UBMS projects serving nearly 7,000 students at a total cost of $33 million. This report is based on participant surveys and student transcripts collected between 1998 and 1999, and again between 2001 and 2002. The evaluation found that UBMS provides intensive academic instruction in math and science, and impact estimates suggest that it improves several student outcomes in high school and college. In addition, preliminary estimates suggest that participation increases the odds of majoring in math or science.