The Career Preparation Assessment (CPA) portfolio is an interdisciplinary, performance-based assessment of skills essential for the post-high school world. The CPA's value as an assessment tool was examined in a pilot test that was conducted in 1996-1997 with six California high schools. The following three data collection activities were conducted to determine the CPA's effectiveness in terms of implementation, student performance/assessment, and whole school change: (1) 8 pilot test teachers and 6 employers of entry-level workers scored the CPA portfolios submitted by 631 students from the 6 high schools; (2) 36 teachers at the 6 schools completed teacher surveys and participated in telephone interviews; and (3) 623 students completed a student survey. Major findings included the following: (1) successful implementation of the CPA and interdisciplinary standards-based assessments requires multiple conditions associated with whole school change; (2) teachers considered the CPA a worthwhile expenditure of time and effort; (3) nearly two-thirds of the students indicated that they would recommend CPA portfolios to other students. (Nineteen tables are included. Appendixes, constituting approximately 40% of this document, contain the following: career preparation standards; data collection instruments; results from the CPA teacher and student surveys; and career preparation assessment rating guide.) (MN)