A public Montessori school is expected to demonstrate high student scores on standardized assessments to succeed in the current school accountability era. A problem for a public Montessori elementary school is how to make sense of the school's high-stakes assessment scores in terms of Montessori's unique educational approach. This case study examined the ways one public Montessori elementary school responded to its high-stakes test scores in the areas of curriculum, instruction, and assessment. The research revealed the ways the principal, teachers, and parents on the school council modified Montessori practices, curriculum, and assessment procedures based on test scores. A quality Montessori education is designed to offer children opportunities to develop both cognitive skills and affective behaviors such as student motivation that will serve them beyond their public school experiences. However, fundamental Montessori practices were modified as a result of the pressure to raise test scores. The impact of the high-stakes assessment era on alternative types of schools must be considered because it is contradictory to support the availability of educational alternatives while at the same time pressuring these schools to conform to strict and narrow measures of success.