To improve student performance, educators have recently adopted non-traditional classroom practices. Yet, as media reports and some research indicate, parents may favor traditional practices. A descriptive case study examined the beliefs of a representative sample of 25 parents of students in grade 11 who studied English in a heterogeneously-grouped American Studies course in a small high school in Southern Maine. Findings suggest that parents' beliefs may not be as traditional as many educators may think and that differences are not always related to social and economic class or educational background. Yet because beliefs are complex and not often explored, parents' expressed preferences or opposition to certain classroom practices can be easily misunderstood. This paper discusses some aspects of these beliefs to show why educators should involve parents in the process of changing instructional practices. Contains 30 references and 2 tables of data. (Author/RS)