The South Washington County school district says a single click resulted in the release of private data on thousands of students last month.
Students' identification numbers, contact information, addresses and bus stop locations and pick-up times were included in a data file that was linked to in a mass email to parents.
In a report on the mistake, the district said an employee accidentally clicked a button to insert a link to the file in the email. The employee repeated the error for a second batch of emails.
South Washington County uses the mass notification system Blackboard to send communications to parents. The report said the employee thought the button was required to send the emails.
The district had the link disabled the next morning, but parents had already received the emails.
The report said the district changed bus stop locations for families that requested a change. The report also said South Washington County will no longer use a mass email service for bus route information. It will instead rely on its password protected, online Parent Portal system.
The district also said it will provide additional training for employees on using Blackboard.