A school bus drifted off of State Route 106 in Mason County yesterday, 6 children on board were not injured. The Washington State Patrol reports that the 46-year-old Belfair woman driving the bus looked in the rearview mirror to check on the kids when the bus drifted onto the soft shoulder 6 miles West of Belfair and was pulled into the ditch at 3:12 Monday afternoon. Traffic was backed up through the area for about 3 hours. A cause and any charges stemming from the accident remain under investigation.