About 69 percent of low-income Arizona children are not enrolled in preschool, and not on track in cognitive knowledge and skills, according to a new report by the Annie E. Casey Foundation.

The study also found that more than 433,000 of kids in the state under the age of eight live in low-income households.

“The first eight years of a child’s life are incredibly important, because the brain architecture is being built," said Dana Naimark, president and CEO of the Children’s Action Alliance, an Arizona advocacy group. "And, what that means is as the child develops and learns, especially in the first three years, their brain cells are developing their neural synapse and that affects how they learn throughout their lives,"

Naimark said children who aren’t enrolled in preschool often are behind in starting kindergarten, as opposed to kids who did go to preschool.

Arizona's Head Start program, which is part of Tucson's Child-Parent Centers, is a preschool program for low-income families. They serve about 22,000 children in the state, according to the Arizona Department of Education.

Naimark said the program has a long waiting list.