I haven't done one of these in a while, let's see what I can come up with!
For the purposes of my sanity, I am following actual chronological time, and therefore including the year that Dean spent with Lisa.
1994 - Sam has probably already been invited to spend Thanksgiving with his friend Stephanie and her family. He's been attending a school called McKinley for nearly two weeks.
1997 - Sam and Dean attend Truman High in Fairfax, Indiana, or, perhaps have just left.
2003 - This is the last week Sam spends with his friend Brady while Brady is still actually Brady.
2005 - Sam and Dean are either in Manitoc, Wisconsin, investigating drownings, or else they have just left.
2006 - It is around this time that Dean tells Sam about their father's final words to Dean.
2007 - Unknown (Possibly hunting vampires while simultaneously being hunted by Gordon)
2008 - It's been two days since Dean told Sam about what happened to him in Hell. They have been working non-stop since.
2009 - Unknown (Possibly trapped in TV-Land by the Trickster, or possibly at a Supernatural Convention.)
2010 - Dean rakes leaves, works in construction, and secretly tries to find a way to rescue Sam, as he tries to live a normal life with Lisa and Ben Braedan in Cicero, Indiana. Meanwhile, Sam's body and brain hunt, while Sam's soul suffers.
2011 - Dean and Sam's body are getting tired of being Crowley's errand boys...or at least Dean is, Sam's body probably doesn't actually care. Meanwhile, Sam's soul still suffers.