The South Butler School District is canceling classes beginning Thursday, the day teachers plan to strike if a new contract with the district is not settled.

The district sent parents a letter Friday saying classes except those at the Butler County Area Vocational-Technical School will be canceled beginning Thursday.

The teachers, represented by the South Butler County Education Association, have been working under terms of their last contract, which expired in 2014. The union issued a strike notice last week saying they would strike if a new contract isn't settled by Thursday.

Negotiating sessions were held this week and more are scheduled for next week.

The district said it will keep parents up to date on contract developments through its website and the media, and encouraged parents to monitor the website.

The district regular and modified transportation will continue to be provided for students in non-public education, special education programs outside the district and vocational and alternative programs.