It's happened to all of us, but thankfully Google has come up with a brilliant solution: Google Tone. Google Tone is an extension which instantly shares URLs (or web addresses) to other computers using sound (you add "extensions" to your Chrome web browser to extend the cool things your browser does).
The process is simple. Once users add the Google Tone extension from the Chrome Web Store, the blue tone button will appear next to each tab. Users then just need to click on the blue button, making sure their computer's speakers are on full volume. Computers in the vicinity will pick up the sound, and the URL will be displayed on the other user's Chrome browser. The user who receives the link will then have an option of clicking that URL to open it. In short, Google Tone broadcasts a URL to any other machine within range. Of course, you would need to make sure all of your students have the Tone extension added to their accounts to ensure the sound is picked up.
Check out this video for a demonstration.
If you are interested in learning more about Google Tone or any other Google app or extension, please contact your ETS Coach!