Blender, ZModler, Wings3D, Silo, Anim8tor
there are plenty of free Modeling programms. Would suggest to use Wings3D or Blender, i heard they are quite nice.
Silo , dunno if its still open beta or some, but it only costs 100$ ? dont remember, not alot compared to other progs. Silo Is mainly for Highpoly shaping and stuff. Really lovly.
Milkshape, could be a chancefor you, gmax aswell. But it depends with what you start, really. There is nothing easier to learn. Aslong you are able to learn the basic you are actually able to work on any Application, just you nee to know the hotkeys.
Reck: with gmax you have less abilities to export something or other things. I bet he wants to try how to model, texture and probably render nice pics and export it to something or to share it with people. Let him decide. It was your time, but maybe not his ;P