This study investigated the effects of instructionist (navigational, functional) versus constructionist (adaptive) World Wide Web (WWW) site environments on collaboration, achievement, attitudes, and perceived level of learner controls reported by students after working in cooperative dyads within the different types of Web-based learning environments. Three different versions of an instructional WWW site were developed, corresponding to the different types of interaction strategies. Twelve eighth-grade students (six dyads) were each assigned three similar instructional problems to solve, and they worked within the different Web environments to accomplish their instructional tasks. When the dyads experienced the navigational site, they viewed a main menu with broad topics displayed as hypertext links. When the dyads were assigned to the functional site, they began their exploration with a site-specific search engine. When the dyads experienced the adaptive (constructionist) site, they were instructed to construct a Web site that addressed the instructional problem. Preliminary results indicated a number of differences between the subjects' performance and behavior while experiencing the adaptive site versus the other two treatments. These included spending more time with the material, reporting a higher degree of learner control, a higher perception of interactivity, and an increase in the amount of positive interpersonal interactions. (Author/MES)