.sdf files created in Visual Studio Express 2012

I am working on a small project written in C#, which I am learning.  I am very new at it.  I have created a data base with 3 tables following the instructions in the tutorial, and then copied it over to a separate file in a separate folder.  It has the .sdf extension.  The tutorial then says to start a new project with the actual code in it, so that the database is not part of the solution, etc, but with a reference to the data base in the program where it opens it.  I have done that.  What I would like to know is how to use SQL server, or some program, to read that database, i.e. some kind of utility, so I can verify updates, print the schema, tables, field names and descriptions if I want to, etc.  Does anyone know what program could do that, that would recognize the .sdf extension?   Thanks for any help.