Sunday: Looking for a unique way to spend Father's Day? Join Cantus for its third annual free concert at the Lake Harriet Bandshell. In a partnership with Minnesota Public Radio, the program features perfect songs for summer, from this year's "Covers" concerts, including "Summertime" (George Gershwin), "April Come She Will" (Simon & Garfunkel), "Time of the Season" (The Zombies) and "California Dreamin' " (The Mamas & The Papas). This will be co-founder Tim Takach's final Twin Cities appearance with the male vocal ensemble. (2 p.m. Sun., Lake Harriet Bandshell, 4135 W. Lake Harriet Pkwy., Mpls., free, 612-435-0055,