Washington —- For kids to do better in math, their teachers might have to go back to school.

Elementary-school teachers are poorly prepared by education schools to teach math, finds a study being released today by the National Council on Teacher Quality.

Math relies heavily on cumulative knowledge, making the early years critical.

The study by the nonpartisan research and advocacy group comes a few months after a federal panel reported that U.S. students have widespread difficulty with fractions, a problem that arises in elementary school and prevents children from mastering more complicated topics like algebra later on.

The report looked at 77 elementary education programs around the country, or roughly 5 percent of the institutions that offer undergraduate elementary teacher certification. It found the programs spend too little time on elementary math topics.

Author Julie Greenberg said education students should be taking courses that give them a deeper understanding of arithmetic and multiplication. She said the courses should explain how math concepts build upon each other and why certain ideas need to be emphasized in the classroom.

Teacher candidates know their multiplication tables, but "they don't come to us knowing why multiplication works the way it does," said Denise Mewborn, who heads the University of Georgia department of math and science education. The university was cited in the report for having an "exemplary program," while nine others met basic requirements. The rest offered too little math coursework or coursework that was considered weak, according to the report.

The University of Georgia requires teacher candidates to take courses to help them understand concepts underlying elementary-school math, as well as math courses not designed for teachers.

The report found significant differences in the number and kind of courses required by each education program.

Education schools also are not being selective enough, the report said. Most require applicants to take an admissions test, usually around their sophomore year of college. But the test, which typically includes reading, writing and math sections, is far too easy, according to the report.

"Almost anyone can get in. Compared to the admissions standards found in other countries, American education schools set exceedingly low expectations for the mathematics knowledge that aspiring teachers must demonstrate," said the report.

U.S. children often fall in the middle or bottom of the pack when compared to other students on international math tests.

Jane West, vice president of government relations for the American Association of Colleges for Teacher Education, said her organization had not received a copy of the report Wednesday.