Computer labs in which students work through assignments using specialized software and/or hardware play a critical role in computing education and in STEM education in general. Traditionally these computer labs have been carried out in computer centers on campus due to the need for specialized software and/or dedicated hardware. Collaborative labs help students to: (1) learn through experience, (2) leverage the perceptions of their learning partners, and (3) form their own opinions through social constructivism. The evidence to date is that collaborative labs consistently demonstrate positive effects on student achievement, self-esteem, and attitude toward learning. Advances in cloud computing and virtualization technologies enable students to complete labs on virtualized resources remotely through the Internet. However, while virtual computer labs provide anywhere, anytime, on-demand access to specialized software and hardware, the virtual workspaces to which students are assigned lack support for sharing, causing the collaborative aspect of learning to be lost. This project serves the national interest in producing a highly-qualified STEM workforce by developing and evaluating an environment that supports collaborative learning in cloud-based virtual computer labs.<br/><br/>The goal of this project is to integrate three models of virtual collaboration into a collaborative lab software tool: shared remote collaboration, virtual study rooms, and a virtual tutoring center. The environment will allow students to reserve virtual computers labs with multiple participants and will support remote real-time collaboration among the participants during a lab. The learning environment will be evaluated in computer science and other STEM discipline courses, and a virtual tutoring center for evaluation will be developed. The collaborative lab environment has the potential to significantly enhance students' collaborative learning in cloud-based virtual computer labs and benefit a wide range of universities and colleges that use virtual computer labs in education. It is expected to support collaborative learning in many STEM disciplines using virtual computer labs, benefitting traditional undergraduates as well as returning adult and distance learning students in both formal and informal settings. The collaborative lab software tool will be distributed as an open source project with all materials, designs, and source code available on a public web site for wide dissemination.