A certificate, awarded by the National Board for Professional Teaching Standards, attesting that a teacher possesses the skills and knowledge of accomplished teaching and meets the National Board standards. To earn a certificate, the teacher must complete a rigorous two-part assessment. The candidate must build a portfolio that provides evidence of good teaching practice. Portfolios include videotapes of classroom teaching, lesson plans, student work samples, and self-evaluative essays. In addition, a candidate participates in a day-long evaluation of his or her knowledge of curriculum design, good teaching practice, assessment of student learning, and subject matter. The two-step process takes approximately one academic year, and most candidates spend about 120 hours on assessment activities.