The Internet, as a communication medium and an interaction platform, is rapidly changing the face of  education. As Internet-based online teaching gains popularity, it has led to the emergence of new educational approaches such as problem-based learning as well as transference and transformation of established teaching practices from traditional classrooms to online environments.

Instead of working face-to-face in groups, online collaboration takes a distributed form. Students from diverse geographical locations form virtual groups and rely on Internet communication technologies to coordinate group processes and carry out group activities.Group interactions are mediated by computer networks. While students are afforded flexibility and new ways of interacting, their group processes and interactive behaviors are also constrained by technical features and functions of the supporting system available in the Internet-based learning environment at the same time.

How can I 'break down the walls of my classroom' without actually having to incur great expenses or construction costs?

An expansion of virtual learning opportunities can provide solutions to some intractable education issues and contribute to schools improving their effectiveness in preparing students for working and living in an increasing globalised and interconnected world.
Once virtual learning is brought to scale, and there is a deeper understanding of the learning and teaching practices associated with this learning approach, it can contribute substantially to solving the following  issues:

Restricted curriculum provision – by giving all students access to the full range of curriculum and to an ever-expanding range of enrichment activities at any time and just about anywhere.

Advancing teacher capability – by enabling excellent teachers to reach more students and enabling teachers to learn from their peers.

The plateauing in learning outcomes – by enabling all students to experience instruction that is delivered by the combination of excellent teaching and excellent online instructional materials.