In the last decade of 19th century, two Kudippallikoodangal were working at chellanam. The owners of these schools were convened by the then Bishop of Cochin and they decided to merge these two Kudippallikoodangal into one. The new school was named St. Mary's LPS, Chellanam and it came under the management of St. Sebastian's Church Chellanam. The first manager was Rev. Fr Kadeparambil, the vicar of the Parish. After nearly 10 years a branch school was opened at Maruvakkadu. In 1924, the school was upgraded into an upper primary school and Rev. Fr. George Herden was the Manager. Later in 1948, the school was upgraded to High school. Since then the school has played a prominent role for the development of the coastal area. The school at present functions in a beautiful three-storied building constructed when Rev Fr Thomas Parathara was the General Manager of the School. Our institution is always blessed with excellent heads of the institution. Our esteemed genre of HMs begins with Shri Rapheal the first Headmaster.