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
this anime is freakin awesome it has a very good storyline thats why i liked it it is based in a city called academy city which the inhabitants are mostly students trying to get supernatural powers and students are categorized in levels the levels are from 0-5, 0 is the lowest people with no powers and 5 is the strongest and only seven people has attained it. The main character is the third strognest level 5 in the city Misaka Mikoto AKA. Tokiwadai's ace "The Railgun". this anime is very sugoi that why i recommend this for anyone so go watch it now!