Project THISTLE (Thinking Skills in Teaching and Learning) was developed by Montclair State College (New Jersey) faculty in collaboration with the Newark, New Jersey, public schools. The project is designed to improve the basic skills of urban college-bound high school students by working with their teachers in an integrated process of curriculum and staff development. An interdisciplinary approach focuses on thinking as an essential, integral part of both subject area learning and "higher order" basic skills development, particulary reading comprehension, analytic writing, and mathematical reasoning and problem solving. Since 1980, more than 100 Newark teachers have participated in the project's program of graduate course work in curriculum development and basic skills instruction, a supervised classroom implementation, and elective professional development activities. Hundreds more have engaged in less intensive project activities. Analysis of pretest and posttest scores of students in grades 10-12 found that the students doubled their annual growth rate in reading comprehension, from an average rate of 6 months in a 10-month period to a rate of 12 months, demonstrating the effectiveness of the project. (MLF)