Voters delivered a solid endorsement of the San Diego Unified School District on Tuesday when they approved a $3.5 billion bond measure for the school system, the district’s largest ever bond measure and the third approved since 2008. About 62 percent of voters said yes to Measure YY, despite critical media coverage of the measure, opposition from watchdog groups and residents and “no” endorsements from multiple organizations, including the San Diego County Taxpayers Association, which only disapproved of one other school bond measure on Tuesday’s ballot.