Students in thousands of schools may get unexpected extended winter vacations because their districts are not prepared for Y2K problems affecting heating, food service and teacher payrolls, the government says.

An Education Department survey released Wednesday said 36 percent of public elementary and secondary school districts are unprepared to fix date-sensitive computer systems. And 39 percent of colleges – where tuition-aid records and longtime research could be threatened – told the department survey they were not ready.