HAVERHILL — With the start of the new school year about six weeks away, Superintendent Margaret Marotta has hired principals to fill vacancies at three city schools.

Shereen Escovitz of Andover, formerly a house principal at Malden High, was hired to lead the Nettle Middle School following the departure of principal Timothy Corkery, who was named principal of the West Middle School in Andover. 

Mary Ellen Lucas of Methuen takes over from Margaret Shepherd, who served as principal of Silver Hill for five years and left the district at the end of this past school year. Lucas previously served as an assistant principal at the Consentino School and most recently, at Silver Hill.

Shannon Gilligan of North Andover will lead the Hunking School in Bradford, following the departure of Shannon Nolan, who was named principal of the Amesbury Elementary School, where she began her job on July 1. 

A screening committee of teachers, parents and School Committeeman Scott Wood interviewed four finalists for the Nettle principalship and ranked them one through four. Those four were then interviewed by Marotta, who offered the position to Escovitz this past weekend, pending contract negotiations. 

Marotta said she was impressed with Escovitz’s experience and expertise in curriculum development and teacher professional development.

Escovitz served as one of four "house principals" at Malden High, overseeing approximately 425 students in grades 9-12. Her educational background also includes working as interim director of STEM disciplines, grades K-12, as a DESE innovation schools fellow, and as a high school math teacher.

Lucas began her new job July 1. She began her career in education in Methuen as a paraprofessional, teacher for fourth and sixth grades, mentor teacher, after school curriculum adviser, and interim associate principal before starting her career in the Haverhill Public School system three years ago as assistant principal at the Consentino School.

Lucas was named assistant principal at Silver Hill in February, before her recent appointment as principal.

Gilligan last served as a school principal 12 years ago. For the past eight years, she served as director of school partnerships for the Teaching and Learning Alliance Inc. of Woburn, where she designed and led plans for improving literacy in public schools.

From 2008-2011, she was coordinator of curriculum instruction and assessment for Somerville Public Schools. She served one year as director of instruction for Marlborough Public Schools and from 2005-2007, she was principal of Castlemont Elementary School, part of the Campbell Union School District in Campbell, California, where she previously served as the district's curriculum coordinator, as a peer support provider and elementary grade teacher.