H.M. Senior Secondry School (popularly known as Happy Model School) was started in year 2000 with 67 students by Children Welfare Education & Social Welfare Society, Gurgaon. Mr. O.P. Arora, a retired horticulturist from Haryana Government, is the president of society. Mr. Arora is a philathropist and hass keen interest in spreading quality education among the masses. It is noteworthy that H.M. Senior Secondry School is most affordable school in Gurgaon. The school has all ultra-modern facilities, its low fees notwithstanding.

The school was affiliated to Haryana Board Of School Education Haryana till 2012. Now the school is affiliated from Central Board Of Secondry Education, Delhi for all India for All India Secondry School Examination (Class X) and All India Senior School Certificate Examination (Class XII) for Science, Commerce and Humanities. The school is an ISO 9001:2008 certified.

The school has come of age and strength of 950 students now. The school has well-educated, trained and experienced teachers. The school teacher ratio never exceeds 20:1. Our classrooms are smart classes with multimedia interactive digital boards. We have well equipped Physics, Chemistry, Biology, Computers and Mathematics laboratories, and a well stocked library. Classrooms are spacious, lighted and ventilated.

The school emphasize on the importance of physical activities and games. It has facilities for indoor and outdoor games like football, cricket, kho-kho, table tennis, badminton, carom, chess etc.