Yeah man, go take some surf lessons or something, or just longboard on the strands, thats what i do! grab a coffee or a bite to eat and cruise some more to just enjoy the atmosphere! There is a cool little skate park in Hermosa i know of, but thats a bit south of beverly hills like 30 mins atleast, but its absolutely beautiful there!
Otherwise go to Disneyland or Six Flags, or go see some cool stuff in hollywood, you can't get bored living there for 80 years dude!