Two graphic computer simulations have been prepared for teaching high school and middle school students about how business organizations and financial systems work: "Parkside," which simulates managing a hotel; and "Guestwear," which simulates managing a clothing manufacturer. Both simulations are based on six principles of constructivist design proposed by the authors: (1) students generate the knowledge as much as possible; (2) knowledge is anchored in authentic situations; (3) cognitive apprenticeship methods are used; (4) knowledge is situated in multiple contexts; (5) cognitive flexibility is created; and (6) students collaborate in knowledge construction. Both simulations are implemented in the "Toolbook" hypermedia authoring environment running in Windows on the schools' computers. Problems with the initial field test were in the area of school and teacher involvement rather than that of student enthusiasm. A second brief test with a receptive teacher suggested that students learned from the simulation and improved in higher level thinking. (Contains 16 references.) (SLD)