That question is asked by many teachers each year.
Enter The Global Audience Project as a solution. This site, created by Google Innovator Brian Costello, works like an online dating service for school projects. There are several searchable databases. Share your projects so others can connect with you as an audience. Find other classes to work collaboratively together. Meet a coach if you are just getting started with breaking your classrooms walls down.
Brian Costello appeared on the TLC Ninja Podcast talking about this project. Watch below: