I applied in-person. The process took 2 months. I interviewed at DAV Public School,Sector-14,Gurgaon (Gurgaon, Haryana) in Mar 2020
Interview
Written test very difficult, concept based. Personal interview and subject expert interview, in depth knowledge required, concepts to be very clear, lastly chairpersons interview, with location and salary discussion and other perks.
I applied through an employee referral. I interviewed at DAV Public School,Sector-14,Gurgaon in Nov 2012
Interview
Interview consisted of questions from various branches of physics especially electronics. Usually the interviewers are professors from Delhi university colleges.
You have to be thorough with your concepts.
Prepare from class 12 and degree books.