What does he want? 2D or 3D?:
To start off with the basics, you animate by saving a keyframe. An animation are the keyframes played in chronological order.
Start by getting a program
There are tons of free, or paid animating programs he should check out.
Blender :
http://www.blender.org/ for 3D animations
Adobe Flash:
http://www.adobe.com/products/flash.html for 2D. This program is great if you want to go big.
Pencil:
http://www.pencil-animation.org/ A tradition 2D animation software for a Macbook. If you want this, invest in a drawing tablet.
Adobe After Effects:
http://www.adobe.com/products/aftereffe ... 09120559:s This is again pricey, but people can make animations out of them.
Animation does not mean you can only do it on computer. Grab a post-it pack, create the "keyframes" on every single post-it. Once done, just flip through it!
The blog
http://vmcomix.blogspot.com/, has some great resources for animators.
Animating is a time consuming activity. Have fun! If you're confused there are tons of tutorials on the internet.
Hopefully this should clarify things.