As mentioned schools/students have free edtions of the Expression Studio through http://www.dreamspark.com - in addition to that small startup companies can join http://www.websitespark.com and recieve Expression Studio as well as Visual Studio, SQL Server and more at close to no cost at all. There is not another company in the world that does more for developers than Microsoft.
As for not enough Silverlight apps/games.. stop complaining about it and make something already.. what are you waiting for?? Compare adoption rates with Flash all you like (Flash has been around close to what 20 years??), anyone notice that Silverlight adoption is dead even/nudging past Java??
No teacher uses C#?? I teach.. I teach C#.. well okay I am by some considered a nobody but, I know my Mother would disagree at least
After a few cracks at doing a full Silverlight site (I kept approaching my designs like I was working in Flash) I finally came up with something creative: http://www.darksilver.ca
Silverlight and Expression Blead are amazing.. if we build it.. well you know the rest..