Does the essay need to fulfill some criteria? Without any limiting factors, the choice of subjects is endless. Some topics that I think might be relevant at the moment are, 1. Shishak Divas (Teacher's day) 2. Mangalyaan (India's Mars program) 3. Manushyon ka vatavaran par prabhav (Human impact on the environment) Some generic topics off the top of my head, 4. Meri priya pustak athva lekhak (My favorite book/author) 5. Patang ki atmakatha (An autobiography of a kite) 6. Bharat ke Tyohar (Festivals of India)