The To Aru Kagaku no Railgun side story is based on Kamachi's original story set in Academy City, a city where about 80% of its 230,000 citizens are students. The story deals with the adventures of Misaka Mikoto, one of the Level 5 psychics in the To Aru Majutsu no Index light novels
Look I hate to admit it but this anime is awesome, it almost has everything that you want in an anime but having said that the only thing which I found lacking was the fact that Touma isn't shown much. I know it's science's turn but still Touma is awesome!!!!!!!!!!!!!!