Freshmen at a newly established laboratory in Iowa State University are using solid modeling and interactive software for three-dimensional visualization in an active learning environment for engineering problem solving and technical communications. A learning center with 22 personal computers and appropriate software supports instruction in two introductory engineering courses. The learning center laboratory is used by 36 students at a time, working with 18 networked high-performance personal computers, in two-student teams. The teams are engaged in such activities as solid modeling, geometric analysis, simulation, and documentation. The two introductory engineering courses most affected by this laboratory are required of all engineering students and, together, have a total enrollment of over 2,200 students a year.