OneDrive for Business is similar to other cloud-based storage system you may have like Dropbox or Google Drive, but it also offers some distinct advantages, especially if you use other Microsoft products. With a OneDrive for Business account all students have access to Microsoft Office Online which allows you to open, edit and share your Word, Excel, PowerPoint, and OneNote files from your web browser.
For more information and a quick video tutorial, please see Microsoft's OneDrive and Office Online overview.