Below are the instructions to get a free 6 month license* of 3ds max or Maya (current version).

* There is a watermark / print banner that appears on your output (I guess). I haven't seen it yet. Someone let me know. Read #9 below.

1. Click here or on the image above to go to the Autodesk Education Community web site.
2. You will need to create a legit account to get access to serial numbers for the software.
3. Sign up for a free student account- Use your real name and school.
4. Once you have your account set up go to the Software Downloads section of the web site.
5. 
6. Download either 3ds max or Maya.
7. The 32bit version of 3ds max appears to be the 6 month license only. The 64 bit version of 3ds max appears to be only good for 30 days. All of the Maya versions appear to be 6 month duration.
8. Also consider Mudbox, AutoCAD, and others available on this same page. Mudbox is listed as only a 30 day working version. But still try out Mudbox. I see it as a much better 3D texture painter than ZBrush. But that's just my opinion.
9. Important Note: The Autodesk Student Version software incorporates all the functionality of our professional licenses, but includes a print banner making the software inappropriate for professional, commercial, or for-profit purposes. Autodesk Student Version software may not be used in the classroom or lab for instructional purposes, or for commercial or for-profit purposes. Annual licenses of Autodesk student software are not eligible for product upgrade or transfer to a commercial license. View print banner sample. View print banner sample.