One day after a Marin County elementary school teacher was charged with repeatedly molesting two children, his body was found floating off Drakes Beach, where his surfboard had washed ashore. Darren Michael Smith, 55, of Fairfax, taught music to children for nearly 24 years, the first 13 at elementary schools in Alameda County and the last 10 at the Mill Valley School District. On March 28, after someone accused Mr. Smith of abusing students, the…