Today?s Sundar English Medium School was started in 2009 as Gokul English medium school (GEMS) at Shivaji nagar, Dahivali, Karjat managed by Jagruthi Shikshan Prathisthan Mandal trust, Karjat. GEMS got relocated to Vachnalya, Posari, Karjat in the year 2012 and subsequently, in the year 2014 to Shivdham, Posari, Karjat.

In the year 2015, Adarsh Public Charitable Trust took over the management of GEMS and named it as Sundar English Medium School and was shifted to the present location i.e. wing A building, on 2 acre plot at Posari , Karjat.

In 2018, the management and the visionary Principal Madhuri Chandrashekhar took drastic steps in upgrading the school.

On 15th August 2020 sponsors Adarsh Public Charitable Trust Society inaugurated the school building wing B, to enhance the school capacity to Standard 10th. CBSE team visited the school and school got C.B.S.E affiliation on 26th October 2020.

Sundar English Medium School is a Nursery to standard X, the first English medium, Co-ed CBSE school at Posari, Karjat