After you have logged into the computer/laptop, Press the three keys: [Alt], [Ctrl] & [Del] at the same time. A screen will pop up. Select “Change a password…” and follow the instructions.
Here is a pretty good YouTube video that goes over the basic features of the iPad. It demonstrates using the latest version of IOS (IOS7) which is the version on all of our iPads. The video is 30 minutes long, but you do not have to watch it all at once