While brainstorming with another designer on how to make a sweatshirt jacket fit better, I shared how I made my first.  Because I didn't have a pattern, or see the last class session, I made mine a little differently.  I cut apart the sweatshirt and quilted pieced fabric to it as usual.  Then I took a fleece jacket pattern to cut the pieces to a usable size and shape before reassembly.  A dropped-shoulder pattern should also work well for this process.