9354539 Henderson The recruitment and retention of under-represented students continues to be one of the primary challenges for higher education. In the field of engineering, women are one of the most under-represented groups, and women continue to have higher attrition rates from engineering than their male peers. We have identified a number of factors which contribute to the differential attrition rates between men and women in engineering and have developed, with preliminary funding from NSF, a novel, collaborative laboratory course to explore "how things work". The course, known as Engineering 25, provides freshman and sophomore women engineering students with the opportunity to disassemble equipment and construct devices to discover the underlying engineering principles involved. The course is unique in that it has, so far, been limited to women engineering students, uses open-ended hands-on projects to stimulate scientific curiosity and alleviate mechanical anxieties, it is based on a collaborative, group exploration approach to learning, and it allows students to explore issues of gender in science and engineering. In the proposed project, we will further develop the course by offering two sections of E25 which will be team-taught by the P.l.s, assess the importance of the various course components (gender make-up, tinkering, collaborative nature, and women's issues), and determine the best way to institutionalize the course. ***y