SSMS "New Query" Behavior On my desktop and on most other instances of Sql Server 2008 R2 and 2012, the default behavior when you right click on a database in the solution explorer of SSMS and choose "New Query" is a new query window opens and changes the database context to the database you clicked on. If you click new query button from the query window, it will open a new query from the same database. 
However, on some other machines, including my boss', the new query opens but the context is the default database (master by default). Clicking new query will likewise open a query in the default database. What is the option to make his instance act like mine?

If I connect to his database from my ssms, it still behaves like it does on his machine (incorrectly).
Max Vernon's suggestion about scripting the logons is spot on. For generic Windows Authentication, the default database tends to be master. Setting a default database for each database instance/logon combination will allow control over what the default database is when launching a new query editor window in SSMS. 

If you use master for windows auth and/or administer many SQL Databases, the CTRL+U shortcut from a new query window -> select database -> hit enter to select and return to query editor will become firmly ingrained in motor memory.