ST. LOUIS (AP) – Some charter schools in St. Louis are starting to worry that their increased popularity is making it difficult for them to stay accessible to low-income students.

The St. Louis Post-Dispatch reports City Garden Montessori, Lafayette Preparatory Academy and The Biome are all working on creating income integration programs specifically for charter schools. The Missouri Charter Public School Association is helping draft a bill that would allow charter schools to set aside a percentage of enrollment spots specifically for low-income students.

Officials at City Garden and Lafayette say that because of neighborhood construction and growing academic success, more affluent white families are enrolling their children while low-income minority students are being edged out.

Officials say those charter schools were always intended to be diverse alternatives to St. Louis Public Schools.