(http://www.starbulls.de/) - visit a game of the local eishockey team.
Climb the Wendelstein or Kampenwand beautiful view!.
Visit the Holzmuseum or the Stadtmuseum. See exhibitions at the Lokschuppen.
Drink coffee at Dinzler or Aran best coffee in town.
Visit the herbstfest Oktoberfest in Rosenheim - information at the city website.