A few students have submitted Google Summer of Code applications - the topics include OpenMoko, OpenOffice, Zope, Haskell, FreeBSD, Ruby - a few more applications will go in today. Some students have done a bit of serious research before submitting their application; whether they get a chance to work on their proposals or not, the very process of identifying a project (out of literally thousands of options) and preparing a writeup would have given them some idea of the breadth and depth of the Free Software world. I am now confident that I can get some of these students to actually contribute code back to the community!
There are a large number of students whom you would never be able to motivate - whatever be the effort you put in. The MCA batches are a good example. These guys have one full semester *free*, just for doing their final year project. What do they do? Summer of Code? No - they prefer getting ready-made projects. This might be because these guys are older than their B.Tech counterparts - as you grow older, the fire within you dies down (well, that's my theory - I hope it doesn't happen in my case).