The New Mexico Portfolio Writing Assessment for grades 4 and 6 (optional for grade 8) is conducted each school year, with a call for each student's best piece in March. This Teacher's Guide provides instructions for implementing the portfolio program throughout the year, in order to ensure standardized application of the process. The portfolio program was first used in 1991-92 as an outgrowth of educational reform efforts in the state. Procedures are summarized for sixth-grade teachers, beginning with a list of materials needed and moving through the scoring process. Scoring guides are included for narrative, expository, descriptive, and analytic writing. Each guide is illustrated with samples of student work at proficiency levels 1 through 6. An addendum contains the required prompts (topics for student writing) for the 1992-93 school year. (Contains 24 references.) (SLD)