The original schools were in Milwaukee—high poverty, high minority, high second language. Since then, the 90-90-90 techniques have been replicated all over the country with multiple language and ethnic groups. The school in California that had the highest achievement gains for two consecutive years, Mead Valley Elementary, was 100% poverty and 99% Latino and second language, and used 90-90-90 techniques. It's also been replicated in deep south rural schools, Native American schools, and many other schools with diverse ethnic and linguistic backgrounds.