The National Council of Teachers of Mathematics (NCTM) Standards recommend that students go beyond memorizing and applying formulas to applying procedures. Students should not only understand mathematics, but also be able to do mathematics. The Core-Plus Mathematics Project (CPMP) is a comprehensive curriculum development project that develops student and teacher materials for a three year high school mathematics curriculum for all students, plus a fourth year course continuing student preparation for college mathematics. This study analyzes students' perceptions and attitudes towards the CPMP curriculum by using the CPMP Student Belief survey. Results showed that CPMP students were significantly more positive about various aspects of the curriculum and their classroom experience than students in traditional classes at the same school. Several elements of the curriculum and instructional model working together appear to explain the positive cognitive and affective results that are emerging from the CPMP field test. (ASK)