25.1 percent of 7th through 12th grade math classes in high-poverty schools are taught by teachers with neither a certification nor a major in the subject. In low-poverty schools, it's 11.4 percent. Those who need the most get the least.
Source: S. Almy and C. Theokas, "Not Prepared for Class: High Poverty Schools Continue to Have Fewer In-Field Teachers," Washington, DC: Education Trust, 2010. Based on an analysis of the 2008 Schools and Staffing Survey, "High poverty schools" in this analysis are schools where at least 55 percent of students are eligible for free- or reduced-price lunch. In "low-poverty schools," at most 15 percent of students are eligible for free- or reduced-price lunch.