Fast forward to today, we have removable hard drives in most Macs now so if you are a fix it type, you can likely replace the drive yourself and save a lot of time. Or the RAM. Logic board and video issues still require a trip to Apple repair but at least it's covered.
But what about iPads? There are no user serviceable parts inside so the biggest issue one has to worry about with the device is if the screen gets broken. But wait, that's not covered under AppleCare....
AppleCare+ is a recent entry into the world of extended coverage of your iPad. For a $49. deductible, the plan covers the device in the usual way, but adds coverage for two drop events over the course of two years. That means if you drop your iPad and smash the screen, you are not out the cost of the device. For about $50 bucks, you will get a replacement.
It's important to back up your data before sending it in though because any time we've had to send in a broken device, we've received a replacement. If you can't back up the data, hopefully the user had iCloud setup or was able to sync (if unsupervised).
Turnaround time was pretty good (about a week) but if you are dealing with a grade of students, it's a good idea to have some iPads (2nd gen or better) on hand to act as loaners until the replacement device arrives. You can restore a backup to the loaner and once the new one comes in, back up the loaner and pull that backup onto the new iPad.