"I was smoking outside the door when I looked up at the sky and suddenly the sky lit up with a bright light and something that looked like the sun fell somewhere to the south of Yekaterinburg, " wrote Sergei Bobunets, quoted by AFP news agency.
Christopher Ray, of the Headmasters' and Headmistresses' Conference, which represents independent school leaders, told BBC News the new system could potentially harm "students who only when they get their AS-level results in Year 12 realise how bright they are, who are perhaps in an underperforming school or college and who suddenly have the self-confidence to aim for the stars".