For rendering large or long jobs, send it to the render farm - a cluster of servers dedicated to rendering.  You can send it from your own laptop or from a school computer.  This way, you can use your own laptop to do the setup work, then let the farm do the heavy lifting.  While it's running, you can do other things on your laptop or free up a public computer for other people to use.

To Setup and Use the Render Farm:

Note: the most common mistake is to use the wrong path for your files.  

For Maya, always send jobs from ScanTemp, not from your C: drive or Desktop.  The render farm can't find your computer to get your files.