PORTLAND (AP) — An educator at Portland’s King Middle School has been named the Maine’s Teacher of the Year.

Education Commissioner Stephen Bowen presented the award to English teacher Karen MacDonald during a surprise assembly Tuesday at the most ethnically and economically diverse middle school in the state.

Bowen said the award celebrates classroom leaders who are preparing children for success in college, careers and civic life.

Last year’s honor went to Shannon Shanning, a special education teacher in Poland. This year’s other finalists were Hartland fourth grade teacher Mary Graziano and Milbridge Elementary School kindergarten teacher Suzen Polk-Hoffses.

Tuesday’s event marked Bowen’s final public event before he departs the Department later this week to become Director of Innovation for the Council of Chief State School Officers.