Kendriya Vidyalayas popularly known as Central Schools, are more or less schools as understood in common parlance. A Sainik School intended essentially to draw young men for being recruited into the National Defence Academy is not an ordinary school. 

The key differences between Kendriya Vidyalayas (KV) and Army/Sainik Schools are:

Curriculum: Kendriya Vidyalayas follow the CBSE curriculum, which is the most widely recognized in India. Army/Sainik schools may follow CBSE, ICSE, or their respective state board curricula. 

Infrastructure: KVs have modern infrastructure like well-equipped classrooms, labs, and IT facilities. Army/Sainik schools have a more traditional approach focused on discipline and military training, with large open spaces for physical activities.

Admission: KV admissions are based on a lottery system, with preference given to children of government employees. Army/Sainik school admissions are more rigorous, with preference given to children of serving or retired army personnel. 

Discipline: Army/Sainik schools have a more regimented lifestyle with early morning drills, parades, and a strong emphasis on discipline. KVs also emphasize discipline but not to the same military-like extent.

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