What, you've lived in Los Angeles all this time and haven't learned to surf? Embrace the California stereotype and sign up for lessons at the surf school at your nearest beach.
Contact info: http://www.yelp.com/search?find_desc=surf+lessons&find_loc=Los+Angeles%2C+CA
Arroyo Seco bike path
Taking a ride through the Arroyo Seco bike path is especially satisfying — the winding route often offers views of those poor schmucks sitting in traffic on the 110 Freeway.
Contact info: Arroyo Seco; http://www.arroyoseco.org/ArroyoSecoBikepath.htm
The Jimmy Kimmel Show is always a blast to attend, but the outdoor mini concerts are an added bonus. Tickets usually go fast, so check in often for upcoming shows.
Contact info: http://abc.go.com/shows/jimmy-kimmel-live