The typical introductory programming course is not an appropriate first computer science course for many students. Initial experiences with programming are often frustrating, resulting in a low rate of successful completion, and focus on syntax rather than providing a representative picture of computer science as a discipline. The paper discusses the design of a preparatory course (CS0) to be taken before the introductory computer science course (CS1) at Utah State University. In the course, students gain mathematical and problem-solving skills while becoming familiar with the computer as a tool and learning how applications can save them time and work. Students are taught basic computer science concepts: data types, internal representation, operators, propositional logic, algorithms, control structures, programs, sub-programs, and recursion. Instruction is through lectures, readings, pencil-and-paper exercises, spreadsheet labs, reading and modifying code, and programming in the language ML, which identifies data type as the data are entered. The paper compares the performance of students in CS1 who took the preparatory course with those who took a course in BASIC prior to CS1. Fifty-three percent of the CSO students who took CS1 achieved A grades in CS1, while only 26% of students who took BASIC before CS1 achieved an A grade in CS1. Results suggest that the preparatory course, with its skill-based approach to computer science, is a better preparation for the traditional first programming experience than a prior programming class. (Contains 13 references.) (SWC)