Educational Portals Central Board of Secondary Education National Council for Educational Research & Training Department of Education, Govt. of India Educational site for teachers National Council for Teacher Educational Homi Bhaba center for Science Education Indian Institute of Technology , Bombay Indira Gandhi National Open University University Grants Commission Department of Science & Technology, Govt. of India Indian Institute of Science, Bangalore National Defence Academy    to know how a thing/ a machine/a body ...part works to ask questions and to know the answers in any subject explanation of with animations & graphics Virtual institute of applied science