(Photo by Nuria Martinez-Keel/Oklahoma Voice)On June 4, 1991, the Legislature passed the first law in the nation that allowed for the creation of a charter school. In the 35 years since, nearly every state has followed suit, and charter enrollment has increased across the country every year. With over 4 million students, charter schools now educate 8% of the public school population and comprise the majority of the school systems in big cities l…