I can open a SQL Server CE 4.0 .sdf file in Visual Studio 2012 and it appears in the Server Explorer. All good.
But as far as I can tell it only shows the regular tables, not system tables.
Is there a way to show system tables?
No, in order to see them, you must type for example:
SELECT * FROM INFORMATION_SCHEMA.TABLES
Which also means you must know the name in advance (the command above lists all available tables by the way)