How does f# decide which file to run on startup?

Be nice, I'm a total newbie to F#. I have created my first console app, and I can't figure out how F# decides which of my .fs files its going to run on startup. Normally apps have an entry point, and the F# forms projects I've seen have an entry point. My console project does not.

It always seems to start with the last file I've added, which is a giant pain. I can't believe its supposed to work this way. I must be doing something wrong.