Oberlin College is developing two laboratory-based introductory courses for the computer science major. The courses generally follow the outline suggested by the ACM Curricular Committee on Computer Science, but give more emphasis to algorithms and conceptual development of the introductory material. The Laboratory sections are used to make the courses more realistic introductions to the broad range of topics covered in computer science, and to speed up and enhance the students' learning of some technical matters that require hands-on experience. The objective is to make the courses more interesting, more useful, and more accurate reflections of the field, and to have a positive effect on the number of women and minorities majoring in computer science.