Maya 2012 objects won't cast shadows
 

So i'm totally new to maya, and I've been doing well so far in figuring out the program, but I'm starting to have major trouble.
none of the objects in my scene will cast a shadow on the ground!
I've tried looking at all of the help options and videos around, but nothing seems to be working.
I attached the file, but i really have no idea where you would start looking for the problem
Any help is appreciated!

You should turn on ray tracking in the render globals as well as ray-traced shadows in your lightShape attributes. That should give you a simple result.

I turned on ray-traced shadows for all of my lights, but i can't find render globals anywhere?

Shadows worked for me using mental ray

Use the help to find render globals . .