This paper describes a National Science Foundation-sponsored project at Louisiana Technological University to develop computer-based laboratories for "hands-on" introductions to major topics of computer science. The underlying strategy is to develop structured laboratory environments that present abstract concepts through the use of computer simulations. These simulations allow students to explore meaningful, but domain limited, problems that are representative of real problems solved by computer scientists and computer engineers. The laboratories focus on: spreadsheets; relational databases; data structures; graphics; the imperative, functional, and logical programming paradigms; and digital logic. Types of laboratories that are candidates for future development include finite state automata; automatic theorem proving; and machine organization and assembly language. In order to insure that the laboratory experiences are useful from a pedagogical standpoint, a rigorous evaluation program will be conducted. Pre- and posttests will be used to measure the changes in, and generalization of, problem solving abilities. Standardized instruments for measuring student attitudes will also be used. (Contains 11 references.) (AEF)